Project description:Staphylococcus epidermidis is a Gram-positive, coagulase-negative (CoNS) bacterium that is carried asymptomatically on the skin and mucous membranes of virtually all human beings. It is a major cause of nosocomial infections and associated with invasive procedures (Méric et al., 2018). Virulent S. epidermidis strains contaminate indwelling medical devices, such as catheters or implants (Sabaté Brescó et al., 2017), showing pathogenicity traits, e.g., biofilm formation, cell toxicity, or methicillin resistance (Méric et al., 2018). Apart from that, even the low-virulent, low-biofilm forming strain of S. epidermidis ATCC 12228 was shown to form a biofilm under decreased oxygen conditions (Uribe-Alvarez et al., 2015). As a member of the skin and mucosal microbiome, S. epidermidis prevents the colonization of Staphylococcus aureus (Otto, 2011). Its well-studied metabolism and the ability to grow on known media make S. epidermidis a possible reconstruction candidate. A reconstruction of a genome-scale metabolic model (GEM) of S. epidermidis was created using CarveMe (Machado et al., 2018) and carefully refined in subsequent manual curation efforts, using the S. epidermidis ATCC 12228 strain sequence. The model was experimentally validated on multiple media under varying growth conditions, such as different carbon sources.
Project description:This study is aimed to isolate marine actinomycetes from sediments from Andaman and the Gulf of Thailand. All 101 marine actinomycetes were screened for anti-biofilm activity. Streptomyces sp. GKU223 showed significantly inhibited biofilm formation of S. aureus. The evaluation of supernatants of anti-biofilm activity produced by Streptomyces sp. GKU223 has been performed. Since the interaction between marine actinomycetes and biofilm forming bacteria has never been investigated, proteomic analysis has been used to identify whole cell proteins involved in anti–biofilm activity. Understanding the interaction at molecular level will lead to sustainably use for anti-biofilm producing marine actinomycetes in pharmaceutical and medicinal applications in the future.
Project description:This study is aimed to isolate marine actinomycetes from sediments from Andaman and the Gulf of Thailand. All 101 marine actinomycetes were screened for anti-biofilm activity. Streptomyces sp. GKU 257-1 showed significantly inhibited biofilm formation of E. coli. The evaluation of supernatants of anti-biofilm activity produced by Streptomyces sp. GKU 257-1 has been performed. Since the interaction between marine actinomycetes and biofilm forming bacteria has never been investigated, proteomic analysis has been used to identify whole cell proteins involved in anti–biofilm activity. Understanding the interaction at molecular level will lead to sustainably use for anti-biofilm producing marine actinomycetes in pharmaceutical and medicinal applications in the future.
Project description:Using an integrated model system for reproducible growth of biofilms, a JPIAMR-funded consortium of researchers* studied the expressed proteome of P. aeruginosa strain MPAO1 under i) planktonic growth, and ii) biofilm formation conditions. The model system included, as a first step, the sequencing and de novo assembly of the complete genome of this opportunistic human pathogen that belongs to the notorious group of Gram-negative ESKAPE pathogens. MPAO1 is also the parental strain for the widely used transposon (Tn) mutant library from the University of Washington. The complete MPAO1 genome sequence turned out to harbor several deletions and insertions compared to the PAO1-UW reference genome including numerous MPAO1-unique genes. As a second step in the model system, a biofilm flow cell based on poly (dimethylsiloxane) (PDMS) was designed to reproducibly study and identify known and novel genes related to biofilm growth and antibiotic resistance (ABR) from the Tn mutant collection. With the complete genome as optimal basis, publicly available TnSeq data were reanalyzed to identify known and novel essential genes. Furthermore, shotgun proteomics data was generated uncovering 1530 (planktonic) and 1728 (biofilm) expressed proteins, respectively, resulting in the identification of 1922 (33.1%) of the 5799 annotated P. aeruginosa MPAO1 proteins. They included proteins known to be differentially expressed during biofilm formation, and proteogenomic evidence for proteins uniquely encoded by MPAO1 as well as novel proteins.
Project description:Here, we report the comparison of transcriptomes of Anabaena sp. PCC7120 and the FurB(Zur) deletion derivative strain (MN38). Anabaena sp PCC7120 is a cyanobacterium that differentiates specialized nitrogen-fixing cells called heterocysts and that is capable of forming biofilms. Our data showed that the deletion of FurB negativily affected the heterocyst development and the biofilm formation. In addition, the RNA-seq data together with gel retardation assays unveiled that FurB is directly involved in the regulation of several genes related to heterocyst development and biofilm formation and other novel functions different from the ones related to the canonical Zur regulon.