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Fulltext Molecular docking of alpha-enolase to elucidate the promising candidates against Streptococcus pneumoniae infection

Hassan M, Baig AA, Attique SA, Abbas S, Khan F, Zahid S, et al.

Daru, 2021 Jun;29(1):73-84.
PMID: 33537864 DOI: 10.1007/s40199-020-00384-3

PURPOSE: To predict potential inhibitors of alpha-enolase to reduce plasminogen binding of Streptococcus pneumoniae (S. pneumoniae) that may lead as an orally active drug. S. pneumoniae remains dominant in causing invasive diseases. Fibrinolytic pathway is a critical factor of S. pneumoniae to invade and progression of disease in the host body. Besides the low mass on the cell surface, alpha-enolase possesses significant plasminogen binding among all exposed proteins.
METHODS: In-silico based drug designing approach was implemented for evaluating potential inhibitors against alpha-enolase based on their binding affinities, energy score and pharmacokinetics. Lipinski's rule of five (LRo5) and Egan's (Brain Or IntestinaL EstimateD) BOILED-Egg methods were executed to predict the best ligand for biological systems.
RESULTS: Molecular docking analysis revealed, Sodium (1,5-dihydroxy-2-oxopyrrolidin-3-yl)-hydroxy-dioxidophosphanium (SF-2312) as a promising inhibitor that fabricates finest attractive charges and conventional hydrogen bonds with S. pneumoniae alpha-enolase. Moreover, the pharmacokinetics of SF-2312 predict it as a therapeutic inhibitor for clinical trials. Like SF-2312, phosphono-acetohydroxamate (PhAH) also constructed adequate interactions at the active site of alpha-enolase, but it predicted less favourable than SF-2312 based on binding affinity.
CONCLUSION: Briefly, SF-2312 and PhAH ligands could inhibit the role of alpha-enolase to restrain plasminogen binding, invasion and progression of S. pneumoniae. As per our investigation and analysis, SF-2312 is the most potent naturally existing inhibitor of S. pneumoniae alpha-enolase in current time.

Matched MeSH terms: Streptococcus pneumoniae/enzymology*
Fulltext Low levels of caries in aggressive periodontitis: A literature review

Sulugodu Ramachandra S

Saudi Dent J, 2014 Apr;26(2):47-9.
PMID: 25408595 DOI: 10.1016/j.sdentj.2013.12.002

This article is a traditional literature review on caries levels in aggressive periodontitis. Aggressive periodontitis generally affects systemically healthy individuals aged <30 years (older individuals can also be affected) and is characterized by a young age of onset, rapid rate of disease progression, and familial aggregation of cases. Dental caries is caused by the dissolution of enamel by acid-producing bacteria present in the plaque biofilm, especially when the biofilm reaches critical mass due to improper oral hygiene. The association between caries level and aggressive periodontitis has long been debated. Initial research indicated that caries levels were high in patients with aggressive periodontitis, but high-quality studies have consistently shown that caries and aggressive periodontitis are inversely related. A recent in vitro study showed that Streptococcus mutans was killed more readily in the saliva of patients with aggressive periodontitis and Aggregatibacter actinomycetemcomitans positivity than in patients with A. actinomycetemcomitans negativity. Other mechanisms possibly explaining the inverse relationship between caries and aggressive periodontitis in cases of Down's syndrome are also discussed in this literature review. The usefulness of caries level in the diagnosis of aggressive periodontitis in developing countries such as India, where the disease is diagnosed primarily on the basis of clinical and radiographic features and familial history is also discussed.

Matched MeSH terms: Streptococcus mutans
Fulltext Development of conventional and real-time multiplex PCR assays for the detection of nosocomial pathogens

Anbazhagan D, Mui WS, Mansor M, Yan GO, Yusof MY, Sekaran SD

Braz J Microbiol, 2011 Apr;42(2):448-58.
PMID: 24031653 DOI: 10.1590/S1517-83822011000200006

Nosocomial infections are major clinical threats to hospitalised patients and represent an important source of morbidity and mortality. It is necessary to develop rapid detection assays of nosocomial pathogens for better prognosis and initiation of antimicrobial therapy in patients. In this study, we present the development of molecular methods for the detection of six common nosocomial pathogens including Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. Conventional multiplex PCR and SYBR Green based real time PCR assays were performed using genus and species specific primers. Blind testing with 300 clinical samples was also carried out. The two assays were found to be sensitive and specific. Eubacterial PCR assay exhibited positive results for 46 clinical isolates from which 43 samples were detected by real time PCR assay. The sensitivity of the assay is about 93.7% in blind test isolates. The PCR results were reconfirmed using the conventional culture method. This assay has the potential to be a rapid, accurate and highly sensitive molecular diagnostic tool for simultaneous detection of Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. This assay has the potential to detect nosocomial pathogens within 5 to 6 hours, helping to initiate infection control measures and appropriate treatment in paediatric and elderly (old aged) patients, pre-and post surgery patients and organ transplant patients and thus reduces their hospitalization duration.

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Transcriptome analysis of Streptococcus pneumoniae treated with the designed antimicrobial peptides, DM3

Le CF, Gudimella R, Razali R, Manikam R, Sekaran SD

Sci Rep, 2016 05 26;6:26828.
PMID: 27225022 DOI: 10.1038/srep26828

In our previous studies, we generated a short 13 amino acid antimicrobial peptide (AMP), DM3, showing potent antipneumococcal activity in vitro and in vivo. Here we analyse the underlying mechanisms of action using Next-Generation transcriptome sequencing of penicillin (PEN)-resistant and PEN-susceptible pneumococci treated with DM3, PEN, and combination of DM3 and PEN (DM3PEN). DM3 induced differential expression in cell wall and cell membrane structural and transmembrane processes. Notably, DM3 altered the expression of competence-induction pathways by upregulating CelA, CelB, and CglA while downregulating Ccs16, ComF, and Ccs4 proteins. Capsular polysaccharide subunits were downregulated in DM3-treated cells, however, it was upregulated in PEN- and DM3PEN-treated groups. Additionally, DM3 altered the amino acids biosynthesis pathways, particularly targeting ribosomal rRNA subunits. Downregulation of cationic AMPs resistance pathway suggests that DM3 treatment could autoenhance pneumococci susceptibility to DM3. Gene enrichment analysis showed that unlike PEN and DM3PEN, DM3 treatment exerted no effect on DNA-binding RNA polymerase activity but observed downregulation of RpoD and RNA polymerase sigma factor. In contrast to DM3, DM3PEN altered the regulation of multiple purine/pyrimidine biosynthesis and metabolic pathways. Future studies based on in vitro experiments are proposed to investigate the key pathways leading to pneumococcal cell death caused by DM3.

Matched MeSH terms: Streptococcus pneumoniae
Burden of bacterial meningitis: a retrospective review on laboratory parameters and factors associated with death in meningitis, kelantan malaysia

Basri R, Zueter AR, Mohamed Z, Alam MK, Norsa'adah B, Hasan SA, et al.

Nagoya J Med Sci, 2015 Feb;77(1-2):59-68.
PMID: 25797971

To describe the clinical characteristics and the risk factors associated with mortality in patients with meningitis. This is a retrospective review of patients diagnosed to have meningitis with positive culture of the cerebrospinal fluid (CSF) specimen. All cases aged 19 > years who were admitted to Hospital USM between January 2004 and December 2011 were included in the study. The CSF results database were obtained from the Department of Medical Microbiology and Parasitology, Hospital USM, Kelantan. A checklist was used to record the clinical characteristics. A total of 125 cases met the inclusion criteria. The age of patients ranged between newborn and 19 years old (Mean±SD, 74.5±80.6 months). The majority of them were males (65.6%). Fever was the most common presentation (73.6%) followed by poor oral intake (48.0%), seizure (36.0%) and headache (24.8%). The mortality rate was 31.2%. Coagulase negative staphylococcus was the most frequent pathogens isolated (21.6%), followed by Acinetobacter spp. (17.6%), Staphylococcus aureus (13.6%), Streptococcus spp. (11.2%) and Klebsiella pneumoniae (6.4%). There were significant association of in-hospital death with age (p=0.020) and conscious level (p=0.001). Infectious meningitis is a big health concern, especially among children. We found that coagulase negative staphylococcus, Acinetobacter species, S. aureus, Streptococcus spp and K. pneumoniae were prevalent in our hospital. These microorganisms were hospital associated pathogens. The 31% mortality linked to hospital acquired meningitis specifies the need for focused physician attention especially among younger aged patients.

Matched MeSH terms: Streptococcus
Fulltext Neonatal group B beta-haemolytic streptococcal infection in Kuala Lumpur

Minhaj AA, Jamal F, Mohamed R

Med J Malaysia, 1980 Dec;35(2):117-21.
PMID: 7022149

First six cases of neonatal group B beta-haemolytic streptococcal sepsis in GHKL & Maternity Hospital K.L. were reported and in one third, it was fatal. Five of the cases were 'early - onset' type and one was 'late - onset' type. While maternal infant transmission of the disease is important in the 'early - onset' type, environmental sources of infection are also significant. No gestational age or birthweight is spared from the disease. Finally, there are cases of 'early - onset' GBS sepsis presenting like hyaline membrane disease of the newborn and it is important to find ways to distinguish them which so far has not been satisfactory.

Matched MeSH terms: Streptococcus agalactiae
Fulltext Microencapsulated frankincense essential oil: a potential remedy and prevention of mouth diseases

Mohamed Soleiman Barre, Fathilah Ali, Mohamed Elwathig Saeed Mirghani, Noor Faizul Hadri Nordin

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):22-22.
MyJurnal

The global burden of disease studies estimated that oral diseases affected half of the world’s population (3.58 billion people) with dental caries (tooth decay) in permanent teeth being the most prevalent condition assessed. On the other hand, the increasing resistance of dental caries towards the available antimicrobials and extensive use of the controversial synthetic chemicals to overcome these problems have attracted the scientific community’s attention to the search for new cost-effective remedies of natural products. Frankincense or Boswellia species are highly import-ant aromatic plants belonging to the Burseraceae family. The present study will focus on an in-vitro anti-inflamma-tion and anti-bacterial activity of Boswellia carterii (BC) Essential oil (EO) encapsulated into the Gum Arabic (GA) polymer. Thus, certain mouth pathogenic bacteria, which are the main contributors to dental caries and gingivitis, namely (Streptococcus mutans and Lactobacillus species), and their in-vitro responses to the defined micro-particles, will pave the way to introduce a new potential remedy to the forth mentioned problems.

Matched MeSH terms: Streptococcus mutans
Fulltext Antibacterial activities of green silver nanoparticles-Strobilanthes crispus (AgNP-SC) against clinically important bacteria

Rohazila Mohamad Hanafiah, Siti Nor Asma Musa, Siti Aisyah Abd Ghafar

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):40-40.
MyJurnal

Introduction: Silver nanoparticles has been proven to be an effective agent for antimicrobial efficacy against bacte-ria, viruses and other eukaryotic microorganisms. Green synthesis is one of the methods that has been developed to synthesize silver nanoparticles in environmentally-friendly conditions. It uses plant extracts as reducing and capping agents. Besides act as reducing and capping agents, bioactives such as phenolic compounds may bind to silver nanoparticles and enhance its medicinal properties. Strobilanthes crispus is a Malaysian native plant. Previous stud-ies had shown that S. crispus contains polyphenols, catechins, alkaloids, caffeine, tannins and vitamins. Therefore, the aim of this study is to determine antibacterial activities of silver nanoparticles-Strobilanthes crispus (AgNP-SC) against clinically important pathogens such as Escherichia coli, Pseudomonas aeruginosa and Streptococcus mutans. Methods: The disc diffusion assay (DDA) was performed to investigate the inhibition zone of AgNps-Sc towards E. coli, P. aeruginosa and S. mutans. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) was used to determine bactericidal/bacteriostatic profile of AgNP- SC against E. coli, P. aeruginosa and S. mu-tans. Results: AgNP-SC (40mg/mL) shows the greatest inhibition properties (12.67±0.6mm) against S. mutans when compared to Strobilanthes crispus leaves extract (6.0±0.001mm) and blank silver nanoparticles (6.0±0.001mm). MIC values for AgNP-SC against S. mutans and E. coli were at 0.625 mg/mL and 1.25 mg/mL, respectively. Whereas the MIC value of AgNP- SC against P. aeruginosa was at 2.5 mg/mL. MBC values of AgNP-SC against E. coli, P. aerugino-sa and S. mutans were at 1.25, 2.5 mg/mL respectively. Results are concentration-dependent, with higher concentra-tion demonstrating better inhibition property. Conclusion: It can be concluded that AgNP-SC possesses bactericidal properties against S. mutans, E. coli and P. aeruginosa.

Matched MeSH terms: Streptococcus mutans
Fulltext Pneumococcal serotype distribution and antibiotic susceptibility in Malaysia: A four-year study (2014-2017) on invasive paediatric isolates

Arushothy R, Ahmad N, Amran F, Hashim R, Samsudin N, Azih CRC

Int J Infect Dis, 2019 Mar;80:129-133.
PMID: 30572022 DOI: 10.1016/j.ijid.2018.12.009

OBJECTIVE: This study was performed to analyze the serotype distribution of Streptococcus pneumoniae causing invasive pneumococcal disease (IPD) in children aged 5 years and under in Malaysia and to assess the antimicrobial resistance.
METHODS: From 2014 to 2017, a total of 245 invasive S. pneumoniae isolates from children ≤5 years of age were received from hospitals all around Malaysia. All isolates were identified and subjected to serotyping and antimicrobial susceptibility testing.
RESULTS: Of the 245 isolates, 117 (48.0%) were from children aged <1year, 46 (19.05%) were from children aged 1-2 years, and 82 (33.0%) were from children aged 2-5 years. The most common serotypes were 14 (26.9%), 6B (19.6%), 19A (11.8%), 6A (10.6%), and 19F (6.9%) and vaccine coverage was 88.2% for PCV13, 64.1% for PCV10, and 63.3% for PCV7. Resistance to penicillin was 0.2% for non-meningitis cases and 22.2% for meningitis cases; erythromycin resistance was reported in 42.9%, co-trimoxazole in 35.9%, and tetracycline in 42.9%.
CONCLUSIONS: Serotypes 14, 6B, 19A, 6A, and 19F were the most common serotypes isolated from children with IPD in Malaysia during this pre-vaccination era. The lack of reports on the serotype distribution has limited action for the implementation of PCV in the national immunization programme (NIP). The information from this study may benefit future policies for the introduction of PCV in the Malaysian NIP and ultimately may reduce the morbidity and mortality among children in Malaysia.

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Gut Bacteria of Water Monitor Lizard (Varanus salvator) Are a Potential Source of Antibacterial Compound(s)

Akbar N, Siddiqui R, Sagathevan K, Iqbal M, Khan NA

Antibiotics (Basel), 2019 Sep 24;8(4).
PMID: 31554316 DOI: 10.3390/antibiotics8040164

For the past few decades, there has been limited progress in the development of novel antibacterials. Previously, we postulated that the gut microbiota of animals residing in polluted environments are a forthcoming supply of antibacterials. Among various species, the water monitor lizard is an interesting species that feeds on organic waste and the carcass of wild animals. Gut microbiota of the water monitor lizard were sequestered, identified and cultivated in RPMI-1640 to produce conditioned medium (CM). Next, the antimicrobial properties of CM were evaluated versus a selection of Gram-negative (Escherichia coli K1, Serratia marcescens,Pseudomonas aeruginosa, Salmonella enterica and Klebsiella pneumoniae) and Gram-positive bacteria (Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus, and Bacillus cereus). CM were partially characterized by heat inactivation at 95°C for 10 min and tested against P. aeruginosa and S. pyogenes. CM were also tested against immortalized human keratinocytes (HaCaT) cells lines. The results demonstrated that gut microbiota isolated from water monitor lizard produced molecules with remarkable bactericidal activities. To determine the identity of the active molecules, CM were subjected to Liquid Chromatography-Mass Spectrometry. Several molecules were identified belonging to the classes of flavonoids, terpenoids, alkaloids, polyhydroxy alkaloids, polyacetylenes, bisphenols, amides, oxylipin and pyrazine derivatives with known broad-spectrum antimicrobial, anti-tumour, anti-oxidant, anti-inflammatory, and analgesic attributes. Furthermore, the detailed analysis of these molecules could lead us to develop effective therapeutic antibacterials.

Matched MeSH terms: Streptococcus pyogenes
Distribution of virulence genes and the molecular epidemiology of Streptococcus pyogenes clinical isolates by emm and multilocus sequence typing methods

Hamzah SNA, Mohd Desa MN, Jasni AS, Mohd Taib N, Masri SN, Hamat RA

Med J Malaysia, 2021 03;76(2):164-170.
PMID: 33742623

BACKGROUND: Streptococcus pyogenes has a variety of virulence factors and the predominant invasive strains differ according to specific emm types and geographical orientation. Although emm typing is commonly used as the gold standard method for the molecular characterisation, multilocus sequence typing (MLST) has become an important tool for comparing the genetic profiles globally. This study aimed to screen selected virulence genes from invasive and non-invasive clinical samples and to characterise the molecular epidemiology by emm typing and MLST methods.
MATERIALS AND METHODS: A total of 42 S. pyogenes isolates from invasive and non-invasive samples collected from two different tertiary hospitals were investigated for the distribution of virulence factors and their molecular epidemiology by emm and multilocus sequence typing methods. Detection of five virulence genes (speA, speB, speJ, ssa and sdaB) was performed using multiplex polymerase chain reaction (PCR) using the standard primers and established protocol. Phylogenetic tree branches were constructed from sequence analysis utilised by neighbour joining method generated from seven housekeeping genes using MEGA X software.
RESULTS: Multiplex PCR analysis revealed that sdaB/speF (78.6%) and speB (61.9%) were the predominant virulence genes. Regardless of the type of invasiveness, diverse distribution of emm types/subtypes was noted which comprised of 27 different emm types/subtypes. The predominant emm types/subtypes were emm63 and emm18 with each gene accounted for 11.8% whereas 12% for each gene was noted for emm28, emm97.4 and emm91. The MLST revealed that the main sequence type (ST) in invasive samples was ST402 (17.7%) while ST473 and ST318 (12% for each ST) were the major types in non-invasive samples. Out of 18 virulotypes, Virulotype A (five genes, 55.6%) and Virulotype B (two genes, 27.8%) were the major virulotypes found in this study. Phylogenetic analysis indicated the presence of seven different clusters of S. pyogenes. Interestingly, Cluster VI showed that selected emm/ST types such as emm71/ST318 (n=2), emm70.1/ST318 (n=1), emm44/ST31 (n=1) and emm18/ST442 (n=1) have clustered within a common group (Virulotype A) for both hospitals studied.
CONCLUSION: The present study showed that group A streptococcci (GAS) are genetically diverse and possess virulence genes regardless of their invasiveness. Majority of the GAS exhibited no restricted pattern of virulotypes except for a few distinct clusters. Therefore, it can be concluded that virulotyping is partially useful for characterising a heterogeneous population of GAS in hospitals.

Matched MeSH terms: Streptococcus pyogenes
Pilus islets and the clonal spread of piliated Streptococcus pneumoniae: A review

Dzaraly ND, Muthanna A, Mohd Desa MN, Taib NM, Masri SN, Rahman NIA, et al.

Int J Med Microbiol, 2020 Oct;310(7):151449.
PMID: 33092697 DOI: 10.1016/j.ijmm.2020.151449

Pneumococci are a common cause of severe infections, such as otitis media, pneumonia, meningitis and bacteremia. Pili are detected in a small proportion of pneumococcal population, but these structures have recently been associated with bacterial virulence in humans. Therefore, the epidemiological relationships between pneumococcal pili, serotype and antimicrobial resistance are of interest. This study aims to discuss the virulence contribution of the Streptococcus pneumoniae pili and the epidemiological relationships among the pilus genes, antimicrobial resistance trends, regional serotypes and genotypic variations. Previous reports have characterized the pneumococcal pilus islet as a clonal feature in the pneumococcal serotypes that are covered by the pneumococcal conjugate vaccine (PCV), including serotypes 19A, 19F, 23F and 7F. Many of the pneumococcal molecular epidemiology network (PMEN) clones are piliated isolates that are also strongly associated with a high frequency of multidrug resistance. Most of these piliated pneumococcal isolates belong to a few clonal complexes (CC), such as CC320, CC199, CC271, CC191 and CC156. Additional molecular epidemiology and genomic studies, particularly whole genome sequence analysis (WGS), are needed to develop an in-depth understanding of the piliated pneumococcal isolates.

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Invasive Pneumococcal Pneumonia with Massive Empyema: a case report

Tin Nwe Latt

Journal of Clinical and Health Sciences, 2016;1:41-47.

Although the use of appropriate antibiotics has significantly improved the outcome of pneumonia, severe complications are still encountered. We report here of a case with invasive pneumococcal pneumonia with massive empyema. A 2-year-4-month old girl presented with fever for 8 days and intermittent cough for 2 weeks. On examination, reduced air entry with dullness on percussion was noted on the left lung. Chest ultrasound revealed moderate to gross pleural effusion with septations, for which left thoraco-centesis with insertion of pigtail tube was performed. Streptococcus pneumoniae was detected via polymerase chain reaction (PCR) test in the pleural fluid. Intravenous (IV) benzylpenicillin and ceftriaxone were given together with one course (5 days) of intrapleural urokinase to breakdown the septations. Timely and appropriate management of pneumonia including the use of thrombolytic agent is vital to ensure optimal outcome and reduce the need of invasive procedures in cases with massive empyema. Public awareness of pneumococcal vaccination is also essential as a part of preventive measures.

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Septic arthritis of the knee and necrotizing fasciitis in a young immunocompetent adult: a case report

Miptah HN, Badlishah Sham SF, Lloyd S, Ramli AS

Journal of Clinical and Health Sciences, 2018;3(2):56-61.
MyJurnal

Septic arthritis is uncommon in immunocompetent young adults. It typically presents in individuals with underlying risk factors. Isolation of Group A Streptococcus (GAS) as the causative agent of septic arthritis is usually associated with autoimmune diseases, chronic skin infections or trauma. Here we report a case of a young lady who is immunocompetent without any prior history of trauma, who presented with an abrupt onset of left knee pain and swelling to the emergency department. An initial diagnosis of acute gout was made and she was treated with non-steroidal anti-inflammatory drug (NSAID). She presented again two days later to a primary care clinic with worsening knee pain and severe left calf pain. A clinical diagnosis of septic arthritis was suspected and the patient was urgently referred to the Orthopaedic team. Synovial fluid from the knee joint aspiration showed growth of GAS. A diagnosis of necrotizing fasciitis was also made as the culture taken from the left calf during incision and drainage (I&D) procedure showed a mixed growth. She eventually underwent surgical debridement twice, together with the administration of several courses of intravenous antibiotics leading to her full recovery after 45 days. This case demonstrates the challenge in making a prompt diagnosis of septic arthritis and probable Type II necrotizing fasciitis in an immunocompetent adult without underlying risk factors. Any delay in diagnosis and treatment would have increased the risk of damage to her knee joint and this may be fatal even in a previously healthy young adult.

Matched MeSH terms: Streptococcus pyogenes
Fulltext Carriage of upper respiratory tract pathogens in rural communities of Sarawak, Malaysian Borneo

Morris DE, McNeil H, Hocknell RE, Anderson R, Tuck AC, Tricarico S, et al.

Pneumonia (Nathan), 2021 Apr 25;13(1):6.
PMID: 33894778 DOI: 10.1186/s41479-021-00084-9

INTRODUCTION: Pneumonia is a leading cause of death in Malaysia. Whilst many studies have reported the aetiology of pneumonia in Western countries, the epidemiology of pneumonia in Malaysia remains poorly understood. As carriage is a prerequisite for disease, we sought to improve our understanding of the carriage and antimicrobial resistance (AMR) of respiratory tract pathogens in Malaysia. The rural communities of Sarawak are an understudied part of the Malaysian population and were the focus of this study, allowing us to gain a better understanding of bacterial epidemiology in this population.
METHODS: A population-based survey of bacterial carriage was undertaken in participants of all ages from rural communities in Sarawak, Malaysia. Nasopharyngeal, nasal, mouth and oropharyngeal swabs were taken. Bacteria were isolated from each swab and identified by culture-based methods and antimicrobial susceptibility testing conducted by disk diffusion or E test.
RESULTS: 140 participants were recruited from five rural communities. Klebsiella pneumoniae was most commonly isolated from participants (30.0%), followed by Staphylococcus aureus (20.7%), Streptococcus pneumoniae (10.7%), Haemophilus influenzae (9.3%), Moraxella catarrhalis (6.4%), Pseudomonas aeruginosa (6.4%) and Neisseria meningitidis (5.0%). Of the 21 S. pneumoniae isolated, 33.3 and 14.3% were serotypes included in the 13 valent PCV (PCV13) and 10 valent PCV (PCV10) respectively. 33.8% of all species were resistant to at least one antibiotic, however all bacterial species except S. pneumoniae were susceptible to at least one type of antibiotic.
CONCLUSION: To our knowledge, this is the first bacterial carriage study undertaken in East Malaysia. We provide valuable and timely data regarding the epidemiology and AMR of respiratory pathogens commonly associated with pneumonia. Further surveillance in Malaysia is necessary to monitor changes in the carriage prevalence of upper respiratory tract pathogens and the emergence of AMR, particularly as PCV is added to the National Immunisation Programme (NIP).

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Salivary bacterial shifts in oral leukoplakia resemble the dysbiotic oral cancer bacteriome

Gopinath D, Kunnath Menon R, Chun Wie C, Banerjee M, Panda S, Mandal D, et al.

J Oral Microbiol, 2020 Dec 09;13(1):1857998.
PMID: 33391629 DOI: 10.1080/20002297.2020.1857998

Objective: While some oral carcinomas appear to arise de novo, others develop within long-standing conditions of the oral cavity that have malignant potential, now known as oral potentially malignant disorders (OPMDs). The oral bacteriome associated with OPMD has been studied to a lesser extent than that associated with oral cancer. To characterize the association in detail we compared the bacteriome in whole mouth fluid (WMF) in patients with oral leukoplakia, oral cancer and healthy controls. Methods: WMF bacteriome from 20 leukoplakia patients, 31 patients with oral cancer and 23 healthy controls were profiled using the Illumina MiSeq platform. Sequencing reads were processed using DADA2, and taxonomical classification was performed using the phylogenetic placement method. Sparse Partial Least Squares Regression Discriminant Analysis model was used to identify bacterial taxa that best discriminate the studied groups. Results: We found considerable overlap between the WMF bacteriome of leukoplakia and oral cancer while a clearer separation between healthy controls and the former two disorders was observed. Specifically, the separation was attributed to 14 taxa belonging to the genera Megaspheara, unclassified enterobacteria, Prevotella, Porphyromonas, Rothia and Salmonella, Streptococcus, and Fusobacterium. The most discriminative bacterial genera between leukoplakia and oral cancer were Megasphaera, unclassified Enterobacteriae, Salmonella and Prevotella.Conclusion: Oral bacteria may play a role in the early stages of oral carcinogenesis as a dysbiotic bacteriome is associated with oral leukoplakia and this resembles that of oral cancer more than healthy controls. Our findings may have implications for developing oral cancer prevention strategies targeting early microbial drivers of oral carcinogenesis.

Matched MeSH terms: Streptococcus
Fulltext Influence of miracle fruit (Synsepalum dulcificum) extract and microencapsulated Lactococcus lactis Gh1 on the antioxidant activity and probiotic viability of functional yogurt

Fazilah, N. F., Zani, N. F. A., Wasoh, H., Ariff, A., Halim, M.

International Food Research Journal, 2020;27(4):683-693.
MyJurnal

Nowadays, functional food market is dominated by dairy-based probiotic products, mainly
yogurt. The nutritional values of yogurt can be further enhanced by the inclusion of miracle
fruit (Synsepalum dulcificum) and potential probiotic Lactococcus lactis Gh1. The present
work investigated the anti-oxidative capacity and survivability of probiotic strains of six
yogurts fortified with S. dulcificum pulp extract and encapsulated L. lactis Gh1 (in
alginate-starch coating agent via extrusion technique). The flavonoid contents (TFC) were not
significantly different between yogurts, whereas the phenolic contents (TPC) showed an
increasing trend throughout the storage. Among the yogurts, the one supplemented with both
S. dulcificum and encapsulated L. lactis Gh1 showed the highest TFC (1.18 µg QE/mL) and
TPC (15.382 μg GAE/mL). The antioxidant assay (DPPH) showed a gradual increase on the
first 7 d, but decreased afterward. In comparison, yogurts fortified with S. dulcificum demonstrated higher antioxidant activity (± 80% DPPH inhibition) than the plain yogurts (± 50%
DPPH inhibition). The viability of starter cultures (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) drastically increased during the first week (log 8 ~ 10
CFU/mL) especially for yogurts containing free cell L. lactis, but subsequently decreased ( log
6 ~ 8 CFU/mL). The viability of L. lactis Gh1 in yogurts maintained at high count (log 9.43
and 9.04 CFU/mL) throughout 21 d when it was being encapsulated. In general, the fortification of S. dulcificum extract with microencapsulated L. lactis Gh1 had greatly enhanced the
quality and potential benefits of the functional yogurts.

Matched MeSH terms: Streptococcus thermophilus
Fulltext Serotype distribution of invasive, non-invasive and carried Streptococcus pneumoniae in Malaysia: a meta-analysis

Lister AJJ, Le CF, Cheah ESG, Desa MNM, Cleary DW, Clarke SC

Pneumonia (Nathan), 2021 May 25;13(1):9.
PMID: 34030731 DOI: 10.1186/s41479-021-00086-7

BACKGROUND: Pneumococcal pneumonia is the leading cause of under-five mortality globally. The surveillance of pneumococcal serotypes is therefore vital for informing pneumococcal vaccination policy and programmes. Pneumococcal conjugate vaccines (PCVs) have been available as an option in the private healthcare setting and beginning December 2020, PCV10 was incorporated as part of routine national immunisation programme (NIP) in Malaysia. We searched existing literature on pneumococcal serotype distribution across Malaysia to provide an overall view of this distribution before the implementation of PCV10.
METHODS: Online databases (PubMed, Ovid MEDLINE and Scopus), reference lists of articles identified, and grey literature (Malaysian Ministry of Health website, WHO website) were systematically searched for relevant literature on pneumococcal serotype distribution across Malaysia up to 10th November 2020. No lower date limit was set to maximise the number of target reports returned. Results of serotypes were split by age categories, including ≤5 years, > 5 years and unreported for those that did not specify.
RESULTS: The search returned 18 relevant results, with a total of 2040 isolates. The most common serotypes across all disease types were 19F (n = 313, 15.3% [95%CI: 13.8-17.0]), 23F (n = 166, 8.1% [95%CI: 7.0-9.4]), 14 (n = 166, 8.1% [95%CI: 7.0-9.4]), 6B (n = 163, 8.0% [95%CI: 6.9-9.2]) and 19A (n = 138, 6.8% [95%CI: 5.8-7.9]).
CONCLUSION: Four of the most common serotypes across all isolate sources in Malaysia are covered by PCV10, while PCV13 provides greater serotype coverage in comparison to PCV10. There is still a need for surveillance studies, particularly those investigating serotypes in children under 5 years of age, to monitor vaccine effectiveness and pneumococcal population dynamic following implementation of PCV10 into routine immunisation.

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Thermostable Heptaplex PCR Assay for the Detection of Six Respiratory Bacterial Pathogens

Nik Zuraina NMN, Goni MD, Amalina KN, Hasan H, Mohamad S, Suraiya S

Diagnostics (Basel), 2021 Apr 22;11(5).
PMID: 33922299 DOI: 10.3390/diagnostics11050753

A thermostabilized, multiplex polymerase chain reaction (mPCR) assay was developed in this study for the detection of six respiratory bacterial pathogens. Specific primers were designed for an internal amplification control (IAC) and six target sequences from Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, Mycobacterium tuberculosis, and Haemophilus influenzae. The resultant seven-band positive amplification control (PAC) of this heptaplex PCR assay corresponded to 105 base pairs (bp) of IAC, 202 bp of K. pneumoniae, 293 bp of S. aureus, 349 bp of S. pneumoniae, 444 bp of P. aeruginosa, 505 bp of M. tuberculosis, and 582 bp of H. influenzae. Results found that 6% (w/v) of the stabilizer was optimum to preserve the functional conformation of Taq DNA polymerase enzyme. This assay was stable at ambient temperature for at least 6 months. The sensitivity and specificity of this assay were both 100% when testing on the intended target organisms (n = 119) and non-intended species (n = 57). The mPCR assay developed in this study enabled accurate, rapid, and simple detection of six respiratory bacteria.

Matched MeSH terms: Streptococcus pneumoniae
Fulltext Gut Bacteria of Rattus rattus (Rat) Produce Broad-Spectrum Antibacterial Lipopeptides

Akbar N, Siddiqui R, Iqbal M, Sagathevan K, Kim KS, Habib F, et al.

ACS Omega, 2021 May 11;6(18):12261-12273.
PMID: 34056379 DOI: 10.1021/acsomega.1c01137

Among several animals, Rattus rattus (rat) lives in polluted environments and feeds on organic waste/small invertebrates, suggesting the presence of inherent mechanisms to thwart infections. In this study, we isolated gut bacteria of rats for their antibacterial activities. Using antibacterial assays, the findings showed that the conditioned media from selected bacteria exhibited bactericidal activities against Gram-negative (Escherichia coli K1, Klebsiella pneumoniae, Pseudomonas aeruginosa, Serratia marcescens, and Salmonella enterica) and Gram-positive (Bacillus cereus, methicillin-resistant Staphylococcus aureus, and Streptococcus pyogenes) pathogenic bacteria. The conditioned media retained their antibacterial properties upon heat treatment at boiling temperature for 10 min. Using MTT assays, the conditioned media showed minimal cytotoxic effects against human keratinocyte cells. Active conditioned media were subjected to tandem mass spectrometry, and the results showed that conditioned media from Bacillus subtilis produced a large repertoire of surfactin and iturin A (lipopeptides) molecules. To our knowledge, this is the first report of isolation of lipopeptides from bacteria isolated from the rat gut. In short, these findings are important and provide a platform to develop effective antibacterial drugs.

Matched MeSH terms: Streptococcus pyogenes

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