The plethora of genome sequence information of bacteria in recent times has ushered in many novel strategies for antibacterial drug discovery and facilitated medical science to take up the challenge of the increasing resistance of pathogenic bacteria to current antibiotics. In this study, we adopted subtractive genomics approach to analyze the whole genome sequence of the Fusobacterium nucleatum, a human oral pathogen having association with colorectal cancer. Our study divulged 1,499 proteins of F. nucleatum, which have no homolog's in human genome. These proteins were subjected to screening further by using the Database of Essential Genes (DEG) that resulted in the identification of 32 vitally important proteins for the bacterium. Subsequent analysis of the identified pivotal proteins, using the Kyoto Encyclopedia of Genes and Genomes (KEGG) Automated Annotation Server (KAAS) resulted in sorting 3 key enzymes of F. nucleatum that may be good candidates as potential drug targets, since they are unique for the bacterium and absent in humans. In addition, we have demonstrated the three dimensional structure of these three proteins. Finally, determination of ligand binding sites of the 2 key proteins as well as screening for functional inhibitors that best fitted with the ligands sites were conducted to discover effective novel therapeutic compounds against F. nucleatum.
Anti-Bacterial Agents ; Bacteria ; Binding Sites ; Colonic Neoplasms ; Colorectal Neoplasms ; Computer Simulation* ; Drug Delivery Systems ; Drug Discovery ; Fusobacterium nucleatum* ; Fusobacterium* ; Genes, Essential ; Genome ; Genome, Human ; Genomics ; Humans ; Ligands ; Mass Screening ; Mining* ; Proteome*

Objective To reveal the presence of methicillin resistant Staphylococcus aureus (S. aureus) (MRSA) in poultry samples and to determine the antibiogram pattern against five antibiotics. Methods Samples from different poultry farm of Chittagong city, Bangladesh were examined for S. aureus by different biochemical tests and confirmed as MRSA by identifying the presence of mecA gene using PCR. Antibiotic resistance pattern in S. aureus was determined by antibiotic disk diffusion method. Results In this study, a total of 60 samples (30 from nasal swabs and 30 from cloacal swabs) were used, of which 54 were confirmed as S. aureus by different biochemical tests. Among these, 12 were confirmed as MRSA by detecting mecA gene using PCR. During antibiogram study, both nasal and cloacal samples showed the highest resistance against penicillin-G and the lowest resistance was observed against neomycin. Conclusions Based on the present study, it can be said that different antibiotics are used extensively in poultry that leads to MRSA and is alarming for human health.