ALBERT

Description: A Gram-positive bacterium originating from the surface-sterilized leaf of Paris polyphylla var. yunnanensis (Franch.) was characterized by using a polyphasic approach. The isolate formed yellow, smooth, circular colonies on nutrient agar with 0.2 % starch (NSA). Cells were non-motile, non-sporulating, irregular rods or cocci. Strain CPCC 203535T had the highest 16S rRNA gene sequence similarity to the type strain of Ornithinimicrobium kibberense (96.9 %) and formed the deepest branch in the genus Ornithinimicrobium in the neighbour-joining (NJ) phylogenetic tree based on 16S rRNA gene sequences. The major menaquinones of strain CPCC 203535T were MK-8(H4), MK-8(H2) and MK-8. The peptidoglycan contained ornithine as the diagnostic diamino acid. The polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylinositol (PI) and unknown lipid (UL). The major fatty acids iso-C14 : 0, iso-C15 : 0, iso-C16 : 0 and anteiso-C15 : 0 were consistent with the fatty acid patterns reported for members of the genus Ornithinimicrobium . The DNA G+C composition is 71.4 mol%. The results of physiological and biochemical tests allowed phenotypic differentiation of strain CPCC 203535T from its closest phylogenetic species in the genus Ornithinimicrobium . Strain CPCC 203535T represents a novel species of the genus Ornithinimicrobium , for which the name Ornithinimicrobium flavum sp. nov. is proposed, with CPCC 203535T (=NBRC 109452 T=KCTC 29164T) as the type strain.

Description: Polymeric carbohydrates are abundant and their recycling by microbes is a key process of the ocean carbon cycle. A deeper analysis of carbohydrate-active enzymes (CAZymes) can offer a window into the mechanisms of microbial communities to degrade carbohydrates in the ocean. In this study, metagenomic genes encoding microbial CAZymes and sugar transporter systems were predicted to assess the microbial glycan niches and functional potentials of glycan utilization in the inner shelf of the Pearl River Estuary (PRE). The CAZymes gene compositions were significantly different between in free-living (0.2–3 μm, FL) and particle-associated (〉3 μm, PA) bacteria of the water column and between water and surface sediments, reflecting glycan niche separation on size fraction and selective degradation in depth. Proteobacteria and Bacteroidota had the highest abundance and glycan niche width of CAZymes genes, respectively. At the genus level, Alteromonas (Gammaproteobacteria) exhibited the greatest abundance and glycan niche width of CAZymes genes and were marked by a high abundance of periplasmic transporter protein TonB and members of the major facilitator superfamily (MFS). The increasing contribution of genes encoding CAZymes and transporters for Alteromonas in bottom water contrasted to surface water and their metabolism are tightly related with particulate carbohydrates (pectin, alginate, starch, lignin-cellulose, chitin, and peptidoglycan) rather than on the utilization of ambient-water DOC. Candidatus Pelagibacter (Alphaproteobacteria) had a narrow glycan niche and was primarily preferred for nitrogen-containing carbohydrates, while their abundant sugar ABC (ATP binding cassette) transporter supported the scavenging mode for carbohydrate assimilation. Planctomycetota, Verrucomicrobiota, and Bacteroidota had similar potential glycan niches in the consumption of the main component of transparent exopolymer particles (sulfated fucose and rhamnose containing polysaccharide and sulfated-N-glycan), developing considerable niche overlap among these taxa. The most abundant CAZymes and transporter genes as well as the widest glycan niche in the abundant bacterial taxa implied their potential key roles on the organic carbon utilization, and the high degree of glycan niches separation and polysaccharide composition importantly influenced bacterial communities in the coastal waters of PRE. These findings expand the current understanding of the organic carbon biotransformation, underlying the size-fractionated glycan niche separation near the estuarine system.