Project description:The Gram-negative, flagellated, anaerobic, crescent-shaped bacterium Selenomonas sputigena is a potential human periodontal pathogen. Information on its virulence factors and underlying pathogenicity mechanisms is scarce. Here we show for the first time that S. sputigena produces a diversely and heavily O-glycosylated flagellin C9LY14 as a major cellular protein, which carries various hitherto undescribed rhamnose- and N acetylglucosamine-linked O-glycans in the range from mono- to hexasaccharides. A comprehensive glycomic and glycoproteomic assessment revealed extensive glycan macro- and microheterogeneity on 20 unique glycopeptide species. From the multiple sites of glycosylation, five were unambiguously identified on the 437-amino acid C9LY14 protein (Thr149, Ser182, Thr199, Thr259, and Ser334). The O-glycans additionally showed modifications by methylation and acetylation. This is the first report on O-linked flagellin glycosylation in S. sputigena, revealing that C9LY14 is one of the most heavily glycosylated flagellins described to date.
Project description:In this study the transcriptomes of Acinetobacter baumannii strains ATCC 17978 and 17978hm were compared. Strain 17978hm is a hns knockout derivative of strain ATCC 17978. Strain 17978hm displays a hyper-motile phenotype on semi-solid Mueller-Hinton (MH) media (0.25% agar). ATCC 17978 and 17978hm from an 37C overnight culture were transferred to the centre of the semi-solid MH plate and incubated at 37C for 8 hours. Only 17978hm cells displayed a motile phenotype and covered the complete surface of the plate. These motile 17978hm cells and the non-motile wild-type ATCC 17978 cells were harvested and RNA was isolated. The comparative transcriptome analysis was performed using the FairPlay labeling kit and a custom made Agilent MicroArray with probes designed to coding regions of the ATCC 17978 genome. The data was analyzed using Agilent GeneSpring GX9 and the significance analysis of microarray MS Excel add-on.
Project description:Corynebacterium glutamicum strain ATCC 21831 is a producer of L-arginine that was created by random mutagenesis. It is resistant to the arginine structural analogue canavanine. In order to identify potential bottlenecks in the biosynthetic pathway that leads to this industrially important amino acid, relative metabolite abundances of biosynthetic intermediates were determined in comparison to the type strain ATCC 13032. An extract of U13C-labeled biomass was used as internal standard, to correct for different ionization efficiencies. Metabolites were identified using the ALLocator web platform.