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Oritavancin - a new semisynthetic lipoglycopeptide agent to tackle the challenge of resistant gram positive pathogens

Das B, Sarkar C, Schachter J

Pak J Pharm Sci, 2013 Sep;26(5):1045-55.
PMID: 24035967

Natural glycopeptide antibiotics like vancomycin and teicoplanin have played a significant role in countering the threat posed by Gram-positive bacterial infections. The emergence of resistance to glycopeptides among enterococci and staphylococci has prompted the search for second-generation drugs of this class and semi-synthetic derivatives are currently under clinical trials. Antimicrobial resistance among Gram-positive organisms has been increasing steadily during the past several decades and the current development of antibiotics falls short of meeting the needs. Oritavancin (LY-333328 diphosphate), a promising novel second-generation semisynthetic lipoglycopeptide, has a mechanism of action similar to that of other glycopeptides. It has concentration-dependent activity against a variety of Gram-positive organisms specially methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate resistant Staphylococcus aureus (VISA), Streptococcus pneumoniae and vancomycin-resistant enterococcus. It is rapidly bactericidal against many species and in particular for enterococci where vancomycin and teicoplanin are only bacteriostatic even against susceptible strains. The pharmacokinetic profile of oritavancin has not been fully described; however, oritavancin has a long half-life of about 195.4 hours and is slowly eliminated by renal means. Oritavancin is not metabolized by the liver in animals. Oritavancin will most probably be prescribed as a once-daily dose and it demonstrates concentration-dependent bactericidal activity. Oritavancin has demonstrated preliminary safety and efficacy in Phase I and II clinical trials. In a Phase III clinical trial, oritavancin has achieved the primary efficacy end point in the treatment of complicated Gram-positive skin and skin-structure infections. To date, adverse events have been mild and limited; the most common being administration site complaints, headache, rhinitis, dry skin, pain, increases in liver transaminases and accumulation of free cholesterol and phospholipids in phagocytic (macrophages) and nonphagocytic (fibroblast) cells. Oritavancin appears to be a promising antimicrobial alternative to vancomycin (with additional activity against Staphylococcus and Enterococcus resistant to vancomycin) for the treatment of complicated Gram-positive skin and skin-structure infections. Additional clinical data are required to fully explore its use.

Matched MeSH terms: Glycopeptides/administration & dosage; Glycopeptides/adverse effects; Glycopeptides/pharmacokinetics; Glycopeptides/therapeutic use*; Glycopeptides/chemistry
Recovery of value-added glycopeptides from edible bird's nest (EBN) co-products: enzymatic hydrolysis, physicochemical characteristics and bioactivity

Ling JWA, Chang LS, Babji AS, Lim SJ

J Sci Food Agric, 2020 Oct;100(13):4714-4722.
PMID: 32468613 DOI: 10.1002/jsfa.10530

BACKGROUND: Processing of edible bird's nest (EBN) requires extensive washing to remove impurities and produces huge amounts of EBN co-products, which contain mainly feathers with glycoproteins attached, which are usually discarded. This study was conducted to recover the valuable EBN glycoproteins from the waste material. Enzymatic hydrolysis was applied to recover EBN glycopeptides from EBN co-products (EBNcoP ) and processed cleaned EBN (EBNclean ) was used as control, which were then freeze-dried into EBN hydrolysates (EBNhcoP and EBNhclean , respectively).
RESULTS: The recovery yield for EBNhclean and EBNhcoP were 89.09 ± 0.01% and 47.64 ± 0.26%, respectively, indicating nearly 50% of glycopeptide can be recovered from the waste material. Meanwhile, N-acetylneuraminic acid, a major acid sugar in EBN glycoproteins, of EBNhcoP increased by 229% from 58.6 ± 3.9 to 192.9 ± 3.1 g kg-1 , indicating the enzymatic hydrolysis removed impurities and thus enhanced the N-acetylneuraminic acid content. Total soluble protein was more than 330 g kg-1 for all the samples. Colour parameter showed that hydrolysate samples have greater L* (lightness) values. Chroma result indicates the intensity of all the samples were low (

Matched MeSH terms: Glycopeptides/isolation & purification; Glycopeptides/chemistry*
Enzymatic hydrolysis: Sialylated mucin (SiaMuc) glycoprotein of edible swiftlet's nest (ESN) and its molecular weight distribution as bioactive ESN SiaMuc-glycopeptide hydrolysate

Hui Yan T, Lim SJ, Babji AS, Rawi MH, Sarbini SR

Int J Biol Macromol, 2021 Apr 01;175:422-431.
PMID: 33561458 DOI: 10.1016/j.ijbiomac.2021.02.007

Bioactive edible swiftlet's nest (ESN) sialylated-mucin (SiaMuc) hydrolysate is produced by alcalase hydrolysis. Enzymatic hydrolysis of ESN breakdown high-valued ESN SiaMuc-glycoprotein into bioactive SiaMuc-glycopeptide. This is a breakthrough for the issue of insolubility and low extraction rate in ESN, and even increases the bioavailability of ESN nutritional functionality and health benefits. Hydrolysis of ESN SiaMuc-glycoprotein was performed for 1 to 4 h and its effect on physicochemical properties, molecular weight (MW) distribution, SiaMuc-glycoprotein and glycopeptide integrity were determined. Other than improvement in solubility and bioavailability as SiaMuc-glycopeptide, results from SDS-PAGE revealed that MW of SiaMuc-glycoprotein decreased from 42.0-148.8 kDa to 17.7-142.7 kDa with increasing hydrolysis period. Further hydrolysis from maximized DH (90 min) showed an insignificant effect on the MW of ESN SiaMuc-glycopeptide and remained constant at 15.2 kDa. This highlights that enzymatic hydrolysis only influences macro SiaMuc-glycoprotein fractions (142.7, 115.3 and 102.7 kDa), while the majority of SiaMuc-glycopeptide fractions from 36.6-98.6 kDa remained intact. Conclusively, alcalase hydrolysis of ESN showed high recovery in the form of bioactive ESN SiaMuc-glycopeptide. Therefore, enzymatic biotechnology is an economic alternative applicable on ESN that broaden industrial utilization by reducing the MW without destroying the quality of bioactive SiaMuc-glycoprotein.

Matched MeSH terms: Glycopeptides
Fulltext Screening and detection of heterogenous vancomycin intermediate Staphylococcus aureus in Hospital Kuala Lumpur Malaysia, using the glycopeptide resistance detection Etest and population analysis profiling

Ramli SR, Neoh HM, Aziz MN, Hussin S

Infect Dis Rep, 2012 Jan 2;4(1):e20.
PMID: 24470927 DOI: 10.4081/idr.2012.e20

In a 3-month study done in Hospital Kuala Lumpur (HKL), 7 out of 320 methicillin resistant Staphylococcus aureus isolates were confirmed as heterogeneous vancomycin intermediate S. aureus (hVISA) using the glycopeptide resistance detection e-test and population analysis, giving a prevalence rate of 2.19%. This is the first report of hVISA in Malaysia.

Matched MeSH terms: Glycopeptides
An unbiased approach for analysis of protein glycosylation and application to influenza vaccine hemagglutinin

An Y, Cipollo JF

Anal Biochem, 2011 Aug 1;415(1):67-80.
PMID: 21545787 DOI: 10.1016/j.ab.2011.04.018

Here a mass spectrometry-based platform for the analysis of glycoproteins is presented. Glycopeptides and released glycans are analyzed, the former by quadrupole orthogonal time-of-flight liquid chromatography/mass spectrometry (QoTOF LC/MS) and the latter by permethylation analysis using matrix-assisted laser desorption/ionization (MALDI)-TOF MS. QoTOF LC/MS analysis reveals the stochastic distribution of glycoforms at occupied sequons, and the latter provides a semiquantitative assessment of overall protein glycosylation. Hydrophilic interaction chromatography (HILIC) was used for unbiased enrichment of glycopeptides and was validated using five model N-glycoproteins bearing a wide array of glycans, including high-mannose, complex, and hybrid subtypes such as sulfo and sialyl forms. Sialyl and especially sulfated glycans are difficult to analyze because these substitutions are labile. The conditions used here allow detection of these compounds quantitatively, intact, and in the context of overall glycosylation. As a test case, we analyzed influenza B/Malaysia/2506/2004 hemagglutinin, a component of the 2006-2007 influenza vaccine. It bears 11 glycosylation sites. Approximately 90% of its glycans are high mannose, and 10% are present as complex and hybrid types, including those with sulfate. The stochastic distribution of glycoforms at glycosylation sites is revealed. This platform should have wide applications to glycoproteins in basic sciences and industry because no apparent bias for any glycoforms is observed.

Matched MeSH terms: Glycopeptides/analysis
Fulltext In vitro activity of teicoplanin, vancomycin, A16686, clindamycin, erythromycin and fusidic acid against anaerobic bacteria

Hassan H, O'Hare MD, Felmingham D

Singapore Med J, 1990 Feb;31(1):56-8.
PMID: 2139737

The in vitro activity of teicoplanin and A16686, two new glycopeptide antibiotics was determined against 196 isolates of anaerobic bacteria. The activity of teicoplanin and A16686, in comparison with that of vancomycin, clindamycin, erythromycin and fusidic acid was 2 to 16 times higher against the gram positive anaerobes, namely, Propionibacterium acnes, Clostridium perfringens, Clostridium difficile, Clostridium species, Peptococcus species and Peptostreptococcus species. However, Bacteroides fragilis was resistant to teicoplanin and A16686 while Bacteroides melaninogenicus and Bacteroides bivius were found to be sensitive.

Matched MeSH terms: Glycopeptides/pharmacology
Fulltext Antifreeze Proteins and Their Practical Utilization in Industry, Medicine, and Agriculture

Eskandari A, Leow TC, Rahman MBA, Oslan SN

Biomolecules, 2020 12 09;10(12).
PMID: 33317024 DOI: 10.3390/biom10121649

Antifreeze proteins (AFPs) are specific proteins, glycopeptides, and peptides made by different organisms to allow cells to survive in sub-zero conditions. AFPs function by reducing the water's freezing point and avoiding ice crystals' growth in the frozen stage. Their capability in modifying ice growth leads to the stabilization of ice crystals within a given temperature range and the inhibition of ice recrystallization that decreases the drip loss during thawing. This review presents the potential applications of AFPs from different sources and types. AFPs can be found in diverse sources such as fish, yeast, plants, bacteria, and insects. Various sources reveal different α-helices and β-sheets structures. Recently, analysis of AFPs has been conducted through bioinformatics tools to analyze their functions within proper time. AFPs can be used widely in various aspects of application and have significant industrial functions, encompassing the enhancement of foods' freezing and liquefying properties, protection of frost plants, enhancement of ice cream's texture, cryosurgery, and cryopreservation of cells and tissues. In conclusion, these applications and physical properties of AFPs can be further explored to meet other industrial players. Designing the peptide-based AFP can also be done to subsequently improve its function.

Matched MeSH terms: Glycopeptides