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Fulltext Draft Genome Sequences of Longimonas halophila KCTC 42399 and Longibacter salinarum KCTC 52045

Liew KJ, Teo SC, Shamsir MS, Goh KM

Microbiol Resour Announc, 2019 Nov 14;8(46).
PMID: 31727717 DOI: 10.1128/MRA.01238-19

Longimonas halophila and Longibacter salinarum are type strains of underexplored genera affiliated with Salisaetaceae Herein, we report the draft genome sequences of two strains of these bacteria, L. halophila KCTC 42399 and L. salinarum KCTC 52045, with the intent of broadening knowledge of this family. Genome annotation and gene mining revealed that both bacteria exhibit amylolytic abilities.

Matched MeSH terms: Bacteroidetes
RATIO OF MAIN PHYLOTYPES OF GUT MICROBIOTA IN PATIENTS WITH NON-ALCOHOLIC FATTY LIVER DISEASE DEPENDING ON THE BODY MASS INDEX

Fadieienko GD, Chereliuk NI, Galchinskaya VY

Wiad Lek, 2021;74(3 cz 1):523-528.
PMID: 33813462

OBJECTIVE: The aim: To analyze the status of Gut microbiota (GM) at the level of the main phylotypes in patients with NAFLD, depending on the body mass index (BMI) and gender in comparison with a group of practically healthy individuals.
PATIENTS AND METHODS: Materials and methods: The study involved 120 patients with NAFLD, who were divided into two groups depending on BMI and the control group containing 20 practically healthy individuals.
RESULTS: Results: In patients with NAFLD with comorbid obesity, a statistically significant increase in the relative amount of Firmicutes (52.12 [42.38; 67.39]%) and Firmicutes/Bacteroidetes ratio (3.75 [1.7; 9.5]) against the background of a significant decrease in the amount of Bacteroidetes (13.41 [7.45; 26.07]%); in NAFLD patients with overweight, the relative amount of Firmicutes was 49.39 [37.47; 62.73]%, Firmicutes / Bacteroidetes ratio was 1.98 [1.15; 5.92], and the relative amount of Bacteroidetes was 23.69 [12.11; 36.16]%. In the control group, the distribution of the basic GM phylotypes was significantly different; the relative amount of Bacteroidetes was almost the same as of Firmicutes - 34.65 [24.58; 43.53]% and 29.97 [22.52; 41.75]% respectively, and the Firmicutes/Bacteroidetes ratio was 0.64 [0.52; 1.47].
CONCLUSION: Conclusions: The most statistically significant changes in the composition of IM occur due to the increase in the relative amount of Firmicutes and the ratio of Firmicutes/ Bacteroidetes against the background of a decrease in the relative amount of Bacteroidetes. These changes were directly proportional to the increase in BMI, but had no gender features.

Matched MeSH terms: Bacteroidetes
Fulltext Removal of Microcystis aeruginosa cells using the dead cells of a marine filamentous bacterium, Aureispira sp. CCB-QB1

Furusawa G, Iwamoto K

PeerJ, 2022;10:e12867.
PMID: 35223202 DOI: 10.7717/peerj.12867

Inorganic and synthetic flocculants are widely investigated for removing harmful microalgae, such as Microcystis aeruginosa. However, their toxicity and non-biodegradability are shortcomings. Bioflocculants based on extracellular polysaccharides have attracted much attention as alternative flocculants. However, its high production cost is a limiting factor for applying bioflocculants. Here, we investigate the potential of the dead cells of a marine filamentous bacterium, Aureispira sp. CCB-QB1, as a novel flocculant on M. aeruginosa cells. The removal efficiency of M. aeruginosa cells by the dead cells was measured by mixing and shaking both components in a buffer with 5 mM CaCl2 in different incubation times and concentrations of the dead cells. After that, the minimum effective concentration of CaCl2 was determined. The combination effect of FeCl3 and the dead cells on the removal efficiency was tested. The structure of cell aggregates consisted of the dead cells and M. aeruginosa cells were also observed using a scanning electron microscope. The maximum removal efficiency (75.39%) was reached within 3 min in the presence of CaCl2 when 5 mg/ml of the dead cells (wet cells) were added. The optimal concentration of CaCl2 was 5 mM. The combination of the dead cells and a low concentration of FeCl3 (10 mg/L) with 5 mM of CaCl2 significantly improved the removal efficiency by about 1.2 times (P

Matched MeSH terms: Bacteroidetes
Fulltext Agarolytic bacterium Persicobacter sp. CCB-QB2 exhibited a diauxic growth involving galactose utilization pathway

Furusawa G, Lau NS, Suganthi A, Amirul AA

Microbiologyopen, 2017 02;6(1).
PMID: 27987272 DOI: 10.1002/mbo3.405

The agarolytic bacterium Persicobacter sp. CCB-QB2 was isolated from seaweed (genus Ulva) collected from a coastal area of Malaysia. Here, we report a high-quality draft genome sequence for QB2. The Rapid Annotation using Subsystem Technology (RAST) annotation server identified four β-agarases (PdAgaA, PdAgaB, PdAgaC, and PdAgaD) as well as galK, galE, and phosphoglucomutase, which are related to the Leloir pathway. Interestingly, QB2 exhibited a diauxic growth in the presence of two kinds of nutrients, such as tryptone and agar. In cells grown with agar, the profiles of agarase activity and growth rate were very similar. galK, galE, and phosphoglucomutase genes were highly expressed in the second growth phase of diauxic growth, indicating that QB2 cells use galactose hydrolyzed from agar by its agarases and exhibit nutrient prioritization. This is the first report describing diauxic growth for agarolytic bacteria. QB2 is a potential novel model organism for studying diauxic growth in environmental bacteria.

Matched MeSH terms: Bacteroidetes/genetics; Bacteroidetes/growth & development*; Bacteroidetes/isolation & purification; Bacteroidetes/metabolism*
Crystal structure of a neoagarobiose-producing GH16 family β-agarase from Persicobacter sp. CCB-QB2

Teh AH, Fazli NH, Furusawa G

Appl Microbiol Biotechnol, 2020 Jan;104(2):633-641.
PMID: 31784792 DOI: 10.1007/s00253-019-10237-y

PdAgaC from the marine bacterium Persicobacter sp. CCB-QB2 is a β-agarase belonging to the glycoside hydrolase family 16 (GH16). It is one of only a handful of endo-acting GH16 β-agarases able to degrade agar completely to produce neoagarobiose (NA2). The crystal structure of PdAgaC's catalytic domain, which has one of the highest Vmax value at 2.9 × 103 U/mg, was determined in order to understand its unique mechanism. The catalytic domain is made up of a typical β-jelly roll fold with two additional insertions, and a well-conserved but wider substrate-binding cleft with some minor changes. Among the unique differences, two unconserved residues, Asn226 and Arg286, may potentially contribute additional hydrogen bonds to subsites -1 and +2, respectively, while a third, His185 from one of the additional insertions, may further contribute another bond to subsite +2. These additional hydrogen bonds may probably have enhanced PdAgaC's affinity for short agaro-oligosaccharides such as neoagarotetraose (NA4), rendering it capable of binding NA4 strongly enough for rapid degradation into NA2.

Matched MeSH terms: Bacteroidetes/enzymology*
Microbiota composition of captive bluestreak cleaner wrasse Labroides dimidiatus (Valenciennes, 1839)

Nurul AAN, Danish-Daniel AM, Okomoda VT, Asma NA

Appl Microbiol Biotechnol, 2020 Sep;104(17):7391-7407.
PMID: 32676710 DOI: 10.1007/s00253-020-10781-y

The Labroides dimidiatus is one of the most traded marine ornamental fishes worldwide, yet not much is known about the microflora associated with this fish. This study is designed to investigate the bacteria composition associated with captive L. dimidiatus and its surrounding aquarium water. The fish and carriage water were obtained from well-known ornamental fish suppliers in Terengganu Malaysia. Bacteria present on the skin and in the stomach and the aquarium water were enumerated using culture-independent approaches and next-generation sequencing (NGS) technology. A total of 3,238,564 valid reads and 828 total operational taxonomic units (OTUs) were obtained from the three metagenomic libraries using NGS analysis. Of all the 15 phyla identified in this study, Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria were the most prevalent in all samples. Also, 170 families belonging to 36 bacteria classes were identified. Although many of the bacteria families were common in the skin, gut, and aquarium water (39%), about 26% of the families were exclusive to the aquarium water alone. Therefore, any substantial change in the structure and abundance of microbiota (especially pathogenic bacteria) reported in this study may serve as an early sign for disease infection in the species under captivity. KEY POINTS: • Proteobacteria was the most dominant. • The microbiota was either shared or exclusively in samples.

Matched MeSH terms: Bacteroidetes/genetics
Fulltext Microbiome and ischemic stroke: A systematic review

Lee YT, Mohd Ismail NI, Wei LK

PLoS One, 2021;16(1):e0245038.
PMID: 33439913 DOI: 10.1371/journal.pone.0245038

BACKGROUND: Ischemic stroke is one of the non-communicable diseases that contribute to the significant number of deaths worldwide. However, the relationship between microbiome and ischemic stroke remained unknown. Hence, the objective of this study was to perform systematic review on the relationship between human microbiome and ischemic stroke.
METHODS: A systematic review on ischemic stroke was carried out for all articles obtained from databases until 22nd October 2020. Main findings were extracted from all the eligible studies.
RESULTS: Eighteen eligible studies were included in the systematic review. These studies suggested that aging, inflammation, and different microbial compositions could contribute to ischemic stroke. Phyla Firmicutes and Bacteroidetes also appeared to manipulate post-stroke outcome. The important role of microbiota-derived short-chain fatty acids and trimethylamine N-oxide in ischemic stroke were also highlighted.
CONCLUSIONS: This is the first systematic review that investigates the relationship between microbiome and ischemic stroke. Aging and inflammation contribute to differential microbial compositions and predispose individuals to ischemic stroke.

Matched MeSH terms: Bacteroidetes/isolation & purification
Genomic analyses of five Roseivirga species: Insights into marine adaptation

Selvaratnam C, Thevarajoo S, Goh KM, Chan KG, Chong CS

Mar Genomics, 2018 Apr;38:97-101.
PMID: 29306571 DOI: 10.1016/j.margen.2017.12.008

To date, the genus Roseivirga consists of six species with one subspecies and is one of the least-studied genera among the family Flammeovirgaceae. In order to further explore this genus, the genome sequences of five Roseivirga spp. were compared and described in this study. The Roseivirga genomes have similar sizes in the range of 4.08-4.47Mb with an average of 4.22Mb. Several key proteins related to osmotic stress adaptation were identified in Roseivirga spp. including betaine transporter, choline dehydrogenase, and glutamate synthases. Significant amount of proteins associated with amino acid transport and metabolism were also present in Roseivirga genome. All five Roseivirga spp. were able to grow in medium contained casamino acids (mixture of amino acids) as sole carbon or nitrogen sources. Taken together, these findings suggested the potential role of Roseivirga in decomposing organic nitrogen matter in marine environment.

Matched MeSH terms: Bacteroidetes/genetics*
Fulltext Faecal DNA metabarcoding reveals novel bacterial community patterns of critically endangered Southern River Terrapin, Batagur affinis

Mohd Salleh MH, Esa Y, Ngalimat MS, Chen PN

PeerJ, 2022;10:e12970.
PMID: 35368336 DOI: 10.7717/peerj.12970

Southern River Terrapin, Batagur affinis, is a freshwater turtle listed as critically endangered on the IUCN Red List since 2000. Many studies suggest that faecal DNA metabarcoding can shield light on the host-associated microbial communities that play important roles in host health. Thus, this study aimed to characterise and compare the faecal bacterial community between captive and wild B. affinis using metabarcoding approaches. A total of seven faeces samples were collected from captive (N = 5) and wild (N = 2) adult B. affinis aseptically, crossing the East and West coast of peninsular Malaysia. The DNA was extracted from the faeces samples, and the 16S rRNA gene (V3-V4 region) was amplified using polymerase chain reaction (PCR). The amplicon was further analysed using SILVA and DADA2 pipelines. In total, 297 bacterial communities taxonomic profile (phylum to genus) were determined. Three phyla were found in high abundance in all faeces samples, namely Firmicutes (38.69%), Bacteroidetes (24.52%), and Fusobacteria (6.95%). Proteobacteria were detected in all faeces samples (39.63%), except the wild sample, KBW3. Under genus level, Cetobacteriumwas found as the most abundant genus (67.79%), followed by Bacteroides (24.56%) and Parabacteroides (21.78%). The uncultured genus had the highest abundance (88.51%) even though not detected in the BK31 and KBW2 samples. The potential probiotic genera (75.00%) were discovered to be more dominant in B. affinis faeces samples. Results demonstrated that the captive B. affinis faeces samples have a greater bacterial variety and richness than wild B. affinis faeces samples. This study has established a starting point for future investigation of the gut microbiota of B. affinis.

Matched MeSH terms: Bacteroidetes/genetics
Fulltext Effects of nanoplastics on the gut microbiota of Pacific white shrimp Litopenaeus vannamei

Zhu C, Li Y, Liu G, Abdullah AL, Jiang Q

PeerJ, 2024;12:e16743.
PMID: 38188162 DOI: 10.7717/peerj.16743

Nanoplastics (NPs) are an abundant, long-lasting, and widespread type of environmental pollution that is of increasing concern because of the serious threats they might pose to ecosystems and species. Identifying the ecological effects of plastic pollution requires understanding the effects of NPs on aquatic organisms. Here, we used the Pacific white shrimp (Litopenaeus vannamei) as a model species to investigate whether ingestion of polystyrene NPs affects gut microbes and leads to metabolic changes in L. vannamei. The abundance of Proteobacteria increased and that of Bacteroidota decreased after NPs treatment. Specifically, Vibrio spp., photobacterium spp., Xanthomarina spp., and Acinetobacter spp. increased in abundance, whereas Sulfitobacter spp. and Pseudoalteromonas spp. decreased. Histological observations showed that L. vannamei exposed to NP displayed a significantly lower intestinal fold height and damaged intestinal structures compared with the control group. Exposure to NPs also stimulated alkaline phosphatase, lysozyme, and acid phosphatase activity, resulting in an immune response in L. vannamei. In addition, the content of triglycerides, total cholesterol, and glucose were significantly altered after NP exposure. These results provided significant ecotoxicological data that can be used to better understand the biological fate and effects of NPs in L. vannamei.

Matched MeSH terms: Bacteroidetes
Habitat shapes the gut microbiome diversity of Malayan tigers (Panthera tigris jacksoni) as revealed through metabarcoding 16S rRNA profiling

Gani M, Mohd-Ridwan AR, Sitam FT, Kamarudin Z, Selamat SS, Awang NMZ, et al.

World J Microbiol Biotechnol, 2024 Feb 28;40(4):111.
PMID: 38416247 DOI: 10.1007/s11274-023-03868-x

The gut microbiome refers to the microorganism community living within the digestive tract. The environment plays a crucial role in shaping the gut microbiome composition of animals. The gut microbiome influences the health and behavior of animals, including the critically endangered Malayan tiger (Panthera tigris jacksoni). However, the gut microbiome composition of Malayan tigers, especially those living in their natural habitats, remains poorly understood. To address this knowledge gap, we used next-generation sequencing DNA metabarcoding techniques to analyze the gut microbiome of wild Malayan tigers using fecal samples collected from their natural habitats and in captivity. Our aim was to determine the gut microbiota composition of the Malayan tiger, considering the different types of habitat environments. The results revealed a diverse microbial community within the gut microbiome of Malayan tigers. The prominent phyla that were observed included Firmicutes, Proteobacteria, Actinobacteriota, Fusobacteriota and Bacteroidota. Beta diversity analysis revealed significant differences in gut microbiome composition of Malayan tigers that inhabited oil palm plantations, in villages and protected areas. Diversity analysis also revealed significant difference in the gut microbiome between wild and captive Malayan tigers. However, the distinctions of gut microbiome between wild and captive alpha diversity did not yield significant differences. The differences in microbiome diversity resulted from the interplay of dietary intake and environmental factors. This information will facilitate the establishment of focused conservation approaches and enhance our understanding of the effect of microbiome composition on Malayan tiger health.

Matched MeSH terms: Bacteroidetes
Calcium is required for ixotrophy of Aureispira sp. CCB-QB1

Furusawa G, Hartzell PL, Navaratnam V

Microbiology (Reading), 2015 Oct;161(10):1933-1941.
PMID: 26306656 DOI: 10.1099/mic.0.000158

Ixotrophy is a process that enables certain microbes to prey on other cells. The ability of cells to aggregate or adhere is thought to be a significant initial step in ixotrophy. The gliding, multicellular filamentous bacterium Aureispira sp. CCB-QB1 belongs to the family Saprospiraceae and preys on bacteria such as Vibrio sp. in seawater. Adhesion and cell aggregation were coincident with preying and were hypothesized to play an important role in the ixotrophy in this bacterium. To test this hypothesis, experiments to elucidate the mechanisms of aggregation or adhesion in this bacterium were performed. The ability of Aureispira QB1 to adhere and aggregate to prey bacterium, Vibrio sp., required divalent cations, especially calcium ions. In the presence of calcium, Aureispira QB1 cells captured 99 % of Vibrio sp. cells after 60 min of incubation. Toluidine blue O, which binds acidic polysaccharides, bound to Aureispira QB1 and inhibited adhesion of Aureispira QB1. These results suggest that acidic polysaccharides are needed for aggregation or adhesion of Aureispira and that calcium ions play a significant role in these phenomena.

Matched MeSH terms: Bacteroidetes/metabolism*; Bacteroidetes/physiology*
Identification of polyunsaturated fatty acid and diterpenoid biosynthesis pathways from draft genome of Aureispira sp. CCB-QB1

Furusawa G, Lau NS, Shu-Chien AC, Jaya-Ram A, Amirul AA

Mar Genomics, 2015 Feb;19:39-44.
PMID: 25468060 DOI: 10.1016/j.margen.2014.10.006

The genus Aureispira consisting of two species, Aureispira marina and Aureispira maritima is an arachidonic acid-producing bacterium and produces secondary metabolites. In this study, we isolated a new Aureispira strain, Aureispira sp. CCB-QB1 from coastal area of Penang, Malaysia and the genome sequence of this strain was determined. The draft genome of this strain is composed of 185 contigs for 7,370,077 bases with 35.6% G+C content and contains 5911 protein-coding genes and 76 RNA genes. Linoleoyl-CoA desaturase, the key gene in arachidonic acid biosynthesis, is present in the genome. It was found that this strain uses mevalonate pathway for the synthesis of geranylgeranyl diphosphate (GGPP), which is precursor of diterpenoid, and novel pathway via futalosine for the synthesis of menaquinones. This is the first draft genome sequence of a member of the genus Aureispira.

Matched MeSH terms: Bacteroidetes/genetics*; Bacteroidetes/physiology
Distinctive bacterial communities in the rhizoplane of four tropical tree species

Oh YM, Kim M, Lee-Cruz L, Lai-Hoe A, Go R, Ainuddin N, et al.

Microb Ecol, 2012 Nov;64(4):1018-27.
PMID: 22767122 DOI: 10.1007/s00248-012-0082-2

It is known that the microbial community of the rhizosphere is not only influenced by factors such as root exudates, phenology, and nutrient uptake but also by the plant species. However, studies of bacterial communities associated with tropical rainforest tree root surfaces, or rhizoplane, are lacking. Here, we analyzed the bacterial community of root surfaces of four species of native trees, Agathis borneensis, Dipterocarpus kerrii, Dyera costulata, and Gnetum gnemon, and nearby bulk soils, in a rainforest arboretum in Malaysia, using 454 pyrosequencing of the 16S rRNA gene. The rhizoplane bacterial communities for each of the four tree species sampled clustered separately from one another on an ordination, suggesting that these assemblages are linked to chemical and biological characteristics of the host or possibly to the mycorrhizal fungi present. Bacterial communities of the rhizoplane had various similarities to surrounding bulk soils. Acidobacteria, Alphaproteobacteria, and Betaproteobacteria were dominant in rhizoplane communities and in bulk soils from the same depth (0-10 cm). In contrast, the relative abundance of certain bacterial lineages on the rhizoplane was different from that in bulk soils: Bacteroidetes and Betaproteobacteria, which are known as copiotrophs, were much more abundant in the rhizoplane in comparison to bulk soil. At the genus level, Burkholderia, Acidobacterium, Dyella, and Edaphobacter were more abundant in the rhizoplane. Burkholderia, which are known as both pathogens and mutualists of plants, were especially abundant on the rhizoplane of all tree species sampled. The Burkholderia species present included known mutualists of tropical crops and also known N fixers. The host-specific character of tropical tree rhizoplane bacterial communities may have implications for understanding nutrient cycling, recruitment, and structuring of tree species diversity in tropical forests. Such understanding may prove to be useful in both tropical forestry and conservation.

Matched MeSH terms: Bacteroidetes/classification; Bacteroidetes/genetics; Bacteroidetes/isolation & purification
Proposal to reclassify Roseivirga ehrenbergii (Nedashkovskaya et al., 2008) as Roseivirga seohaensis comb. nov., description of Roseivirga seohaensis subsp. aquiponti subsp. nov. and emendation of the genus Roseivirga

Selvaratnam C, Thevarajoo S, Goh KM, Chan KG, Chong CS

Int J Syst Evol Microbiol, 2016 Dec;66(12):5537-5543.
PMID: 28077207 DOI: 10.1099/ijsem.0.001553

The genus Roseivirga currently includes five species: Roseivirga ehrenbergii, R. echinicomitans, R. spongicola, R. marina and R. maritima. Marinicola seohaensis SW-152T was renamed as Roseivirgaseohaensis SW-152T and then reclassified again as a later heterotypic synonym of R. ehrenbergii KMM 6017T. In this study, based on average nucleotide identity and digital DNA-DNA hybridization values obtained from in silico methods, together with fatty acid analyses and biochemical tests, we propose to reclassify R. ehrenbergii SW-152 as Roseivirga seohaensis comb. nov. (type strain SW-152T=KCTC 1231T=JCM 12600T). In this work, a Gram-negative, rod-shaped, aerobic and pink-pigmented strain designated as D-25T was isolated from seawater (Desaru Beach, Johor, Malaysia). The 16S rRNA gene analysis revealed that strain D-25T was related to the genus Roseivirga. Strain D-25T was found most closely related to R. seohaensis SW-152T based on average nucleotide identity and digital DNA-DNA hybridization values, phenotypic and chemotaxonomic analyses, indicating that these strains belong to the same species. Thus, it is proposed to split the species R.oseivirga seohaensis into two novel subspecies, Roseivirga seohaensissubsp. seohaensis subsp. nov. (type strain SW-152T=KCTC 12312T=JCM 12600T) and Roseivirga seohaensissubsp. aquiponti subsp. nov. (type strain D-25T=KCTC 42709T=DSM 101709T) and to emend the description of the genus Roseivirga.

Matched MeSH terms: Bacteroidetes/classification*; Bacteroidetes/genetics; Bacteroidetes/isolation & purification
Profiles of bacterial assemblages from microplastics of tropical coastal environments

Curren E, Leong SCY

Sci Total Environ, 2019 Mar 10;655:313-320.
PMID: 30471599 DOI: 10.1016/j.scitotenv.2018.11.250

Plastic waste is a global issue of an increasing concern in aquatic ecosystems. Microplastics form a large proportion of plastic pollution in marine environments. Although microplastics are prevalent, their distribution along the coasts of tropical regions is not well studied. Microplastic pieces (1-5 mm) were collected from two distinct regions along the coastlines of Singapore, from the northern coast in the Johor Strait and the southern coast in the Singapore Strait. Microplastics were present in concentrations ranging from 9.20-59.9 particles per kg of dry sand sediment. The majority of microplastics identified were foam particles (55%) and fragments (35%). Microplastics were significantly more abundant on heavily populated beaches compared to pristine beaches. High throughput sequencing was used to profile the communities of bacteria on the surfaces of microplastic particles. The structure of the microbial communities was primarily characterised by Proteobacteria and Bacteroidetes and were distinct across sites. Hydrocarbon-degrading genera such as Erythrobacter were dominant in areas with heavy shipping and pollution. Potential pathogenic genera such as Vibrio and Pseudomonas were also identified. This study highlights the diverse bacterial assemblages present on marine microplastic surfaces and the importance of understanding the bacterial plastisphere.

Matched MeSH terms: Bacteroidetes
Fulltext Isolation of Spirosoma foliorum sp. nov. from the fallen leaf of Acer palmatum by a novel cultivation technique

Han HL, Nurcahyanto DA, Muhammad N, Lee YJ, Nguyen TTH, Kim SG, et al.

Sci Rep, 2023 Sep 06;13(1):14684.
PMID: 37673882 DOI: 10.1038/s41598-023-35108-5

In the effort of isolating novel microbial species, the strain PL0132T was isolated from a fallen leaf under fresh water at a stream, which glided when grown on a tap water medium (without nutrients). The strain was determined to be Gram-negative, strictly aerobic, and rod-shaped, which grew optimally at 25 °C, pH 6-7, and the strain tolerates 1% (w/v) NaCl concentration. The complete genome of strain PL0132T comprises one contig with a sequencing depth of 76×, consisting of 8,853,064 base pairs and the genomic DNA G + C content was 46.7% (genome). 16S rRNA gene sequence analysis revealed that strain PL0132T represents a member of the phylum Bacteroidetes and is affiliated with the genus Spirosoma. Based on genomic, phenotypic, and chemotaxonomic characteristics, the strain PL0132T represents a novel species of the genus Spirosoma, for which the name Spirosoma foliorum sp. nov. is proposed (= KCTC 72228 T = InaCC B1447T).

Matched MeSH terms: Bacteroidetes
Draft genome sequence of Vitellibacter vladivostokensis KMM 3516(T): a protease-producing bacterium

Thevarajoo S, Selvaratnam C, Chan KG, Goh KM, Chong CS

Mar Genomics, 2015 Oct;23:49-50.
PMID: 25957696 DOI: 10.1016/j.margen.2015.04.009

Type strain Vitellibacter vladivostokensis KMM 3516(T) (=NBRC 16718(T)) belongs to the phylum Cytophaga-Flavobacterium-Bacteroides. To date, no genomes of the Vitellibacter spp. have been reported, and their metabolic pathways are unknown. This study reports the draft genome sequence of V. vladivostokensis. Moreover, mining of genes associated with proteolytic enzymes was performed to provide insights for further enzyme characterization.

Matched MeSH terms: Bacteroidetes/genetics*
Fulltext Biogeography of bacterioplankton in the tropical seawaters of Singapore

Lau SC, Zhang R, Brodie EL, Piceno YM, Andersen G, Liu WT

FEMS Microbiol Ecol, 2013 May;84(2):259-69.
PMID: 23237658 DOI: 10.1111/1574-6941.12057

Knowledge about the biogeography of marine bacterioplankton on the global scale in general and in Southeast Asia in particular has been scarce. This study investigated the biogeography of bacterioplankton community in Singapore seawaters. Twelve stations around Singapore island were sampled on different schedules over 1 year. Using PCR-DNA fingerprinting, DNA cloning and sequencing, and microarray hybridization of the 16S rRNA genes, we observed clear spatial variations of bacterioplankton diversity within the small area of the Singapore seas. Water samples collected from the Singapore Strait (south) throughout the year were dominated by DNA sequences affiliated with Cyanobacteria and Alphaproteobacteria that were believed to be associated with the influx of water from the open seas in Southeast Asia. On the contrary, water in the relatively polluted Johor Strait (north) were dominated by Betaproteobacteria, Gammaproteobacteria, and Bacteroidetes and that were presumably associated with river discharge and the relatively eutrophic conditions of the waterway. Bacterioplankton diversity was temporally stable, except for the episodic surge of Pseudoalteromonas, associated with algal blooms. Overall, these results provide valuable insights into the diversity of bacterioplankton communities in Singapore seas and the possible influences of hydrological conditions and anthropogenic activities on the dynamics of the communities.

Matched MeSH terms: Bacteroidetes/genetics; Bacteroidetes/isolation & purification
In vitro gastrointestinal digestion and fecal fermentation reveal the effect of different encapsulation materials on the release, degradation and modulation of gut microbiota of blueberry anthocyanin extract

Wu Y, Han Y, Tao Y, Li D, Xie G, Show PL, et al.

Food Res Int, 2020 06;132:109098.
PMID: 32331662 DOI: 10.1016/j.foodres.2020.109098

In this study, four different selected wall materials (namely gelatin, soy protein isolate, maltodextrin and Arabic gum) were applied for blueberry anthocyanin extract encapsulation. The effect of these wall material types on the release and degradation of anthocyanin and the modulation of gut microbiota during in vitro simulated gastrointestinal digestion and colonic fermentation were investigated. It was found that the encapsulation of anthocyanin extract using appropriate wall material could significantly enhance the colonic accessibility of anthocyanins. Soy protein isolate and gelatin delayed the release of anthocyanins, whereas the other two wall materials displayed no significant effect on the release time of anthocyanins. Gut microbiota mainly metabolized some phenolic compounds such as 4-hydroxycinnamic acid and chlorogenic acid. Meanwhile, different fermented anthocyanin extract microcapsule broth could significantly decrease the composition and abundance of Firmicutes and increase that of Bacteroidetes. Furthermore, the presence of anthocyanin extract microcapsules, especially those encapsulated with soy protein isolate, promoted the biosynthesis of short-chain fatty acids by gut microbiota. It is concluded that, amongst the wall materials studied, soy protein isolate appeared to be a functional and suitable candidate to delay anthocyanin release and prevent disease through the promotion of gut health.

Matched MeSH terms: Bacteroidetes/drug effects; Bacteroidetes/metabolism

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