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Background: Bacillus species are widely distributed in all environments including health care settings and represent one of the highly resistant organisms. Objective: This study aimed to find out the prevalence, molecular characterization of genetic diversity among studied Bacillus species in Egyptian hospitals environment and their antibiotic susceptibility profile. Methods: A total 528 swab samples were collected from different hospitals environment. Isolation and identification were performed according to conventional bacteriological methods, semi-automated and molecular characterization methods. Antimicrobial susceptibility was carried against different groups of antimicrobial agents. Results: The most isolated microorganism was Bacillus spp. (43.2%), followed by coagulase-negative Staphylococci (19.2%), Staphylococcus aureus (15.2%), Enterococus spp. (10.1%), Gram-negative rods (8.9%), and Micrococcus spp.(3.4 %). The most prevalent species, were Bacillus cereus (46.6%) followed by Bacillus subtilus (38.1%) while, Bacillus pumilus was the least (1.1%). A majority of Bacillus isolates (25.6%) were isolated in Internal medicine department followed by Emergency department (18.8%) while operating rooms showed the lowest prevalence rate (4.5%). Antimicrobial susceptibility testing revealed high resistance of Bacillus isolates to βlactams and tetracycline antibiotics. Multi-drug resistance (MDR) isolates which resistance to three or more antibiotics was (21.6%). Susceptibility reports of the 176 Bacillus isolates revealed 45 antibitypes and the most common was antibiotype 31, which included 32 isolates (18.2%), that is resistant to both penicillin and cefoxitin. Conclusions: This study revealed that, dissemination of Bacillus species in study hospital environments with high resistance to β-lactams and tetracycline antibiotics. The molecular analysis revealed the existence of genetic diversity among studied Bacillus isolates. Thus, monitoring the hospital environment is an important tool in the prevention of hospital-associated infection by Bacillus species.

Deletion, together with basic functional and bioinformatic analyses has been carried out on eight novel ORFs discovered during the sequencing of the Saccharomyces cerevisiae genome. Six ORFs (YLL049w, YLL051c, YLL052c, YLL053c, YLL054c and YLL055w) located on the left arm, and one (YLR130c) on the right arm, of chromosome XII, and an eighth ORF (YNL331c) on the left arm of the chromosome XIV, have been investigated. ORFs were deleted by the SFH–PCR gene‐replacement strategy. Basic functional analysis revealed no obvious phenotype for any of the eight ORFs. Bioinformatic analysis, however, revealed possible functions for seven of the ORFs on the basis of the amino acid sequence similarity of their predicted protein products to those of proteins with known functions. ORF YLL051c (FRE6) shows similarity to iron transport proteins, such as ferric reductase. YLL052c and YLL053c appear to be aquaporins. The product of YLL054c (Yll054p) is highly similar to the oleate‐specific transcriptional activator protein (Pip2p), which is involved in the peroxisomal induction pathway (pip). ORF YLL055w is similar to Dal5p, allantoate permease, and may play role in allantoin transport. YLR130c (ZRT2) is a low‐affinity zinc transporter protein. YNL331c is also named AAD14, which is induced by chemicals that induce oxidative stress by depleting the cell of glutathione. Copyright © 2000 John Wiley & Sons, Ltd.