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In Algeria, the issue of antibiotic resistance is on the rise, being the Staphylococcus aureusinfection as a significant concern of hospital-acquired infections. The emergence of antibiotic resistance in this bacterium poses a worldwide challenge. The aim of this study aims to establish the incidence of S aureusstrains in Algeria as well as identify phenotypic and genotypic resistance based on the “mecA” and “nuc” genes. From 2014 to 2017, a total of 185 S aureusstrains were isolated from patients at a hospital in the city of Rouïba, Algiers the number of isolates was slightly higher in males at 58.06% compared to females at 41.94%, resulting in a sex ratio of 1.38. the Oxacillin and Cefoxitin DD test (1 μg oxacillin disk and 30 μg cefoxitin disk) identified 42 strains as resistant. The results indicated high resistance to lactam antibiotics, with penicillin having a 100% resistance rate. There was also significant resistance to oxacillin (51.25%) and cefoxitin (50%). This resistance was frequently associated with resistance to other antibiotic classes, such as aminoglycosides (50%) and Macrolides (28.29%). To confirm methicillin-resistant characteristics, a polymerase chain reaction (PCR) multiplex was conducted on 10 isolates (6 SARM; 4 MSSA) on a phenotypic level. Three isolates tested positive for “mecA,” while 7 were negative. All strains carry the nuc gene, which is specific to S aureus.In Algeria, the incidence of S aureusresistance is slightly lower compared to other countries, but it is increasing over time. It is now more crucial than ever to restrict the proliferation of multidrug-resistant strains and reduce undue antibiotic prescriptions. To achieve this, it is vital to keep updated on the epidemiology of this bacterium and its antibiotic susceptibility. This will enable the formulation of appropriate preventive control measures to manage its progression.

The complete genome sequence of a representative of Group I Clostridium botulinum is described. The genome consists of a chromosome and a plasmid which carry 3650 and 19 predicted genes and reveals unknown ability Clostridium botulinum to degrade chitin and that is adapted to a saprophytic living in soil and aquatic environment.

•It was the first study on genotypic drug-resistance performed in Algeria on multidrug-resistant Mycobacterium tuberculosis(MDR-TB).•MDR-TB isolates showed some rare patterns, which were probably the result of selection and transmission processes inherent to the country.•New and rare mutations or polymorphisms were described in rpoB(deletion 512-513-514), katG(S315R, M126I/ R496L), gidB(V124G, E92A, V139A, G37V) and gyrA(P8A).•This study will enable Sanger sequencing technology to be transferred from France to Algeria.

The glucose-6-phosphate dehydrogenase (EC 1.1.1.49) gene (zwf) of the cyanobacterium Synechococcus PCC 7942 was cloned on a 2.8 kb Hind III fragment. Sequence analysis revealed an ORF of 1572 nucleotides encoding a polypeptide of 524 amino acids which exhibited 41% identity with the glucose-6-phosphate dehydrogenase of Escherichia coli.

Minimalism in microbiology could be interpreted as a reduction in cell size or a reduction in genome content. Three genomes this month illustrate both of these interpretations. Bdellovibrios are small cells, perhaps because the bdellovibrio life cycle involves entering into, and feeding inside, a host bacterium, which is often as small as 1 μm in diameter. However, even small bdellovibrio cells have a relatively large genome of 3.7 Mb, which is presumably necessary to encode the information that is required for their complicated life cycle. By contrast, mycoplasmas and phytoplasmas, which also reside inside a host cell, have a reduced minimal genome content. Examples of mycoplasma and phytoplasma sequences have recently been published, which could provide further insights into the minimal information requirements for microbial life.

Bacteria and archaea are ubiquitous in the environment, and have fundamental roles in the major geochemical cycles, in addition to being important in aspects of the growth of most multicellular eukaryotes, and in modifying human interactions with the environment. Although individual organisms with important roles in these processes can be identified, mixed communities of organisms that are often unculturable are usually involved. Two approaches to a genomic investigation of environmental communities can be envisaged; first, complete analysis of specific important organisms, and second, whole-community shotgun analysis of the entire community. Examples of both approaches are discussed this month.

With the number of published microbial genomes now in excess of 100, any new genome that is sequenced is likely to have a close relative available for comparison. Indeed, it is increasingly difficult to perform any genomic analysis that is not comparative. This should, however, not be seen as a drawback; it is often the case that a large amount of information can be drawn from these comparisons, especially between closely related organisms. Several genome sequences published recently indicate the value of comparisons at the genomic level.

With the number of published microbial genomes now in excess of 100, any new genome that is sequenced is likely to have a close relative available for comparison. Indeed, it is increasingly difficult to perform any genomic analysis that is not comparative. This should, however, not be seen as a drawback; it is often the case that a large amount of information can be drawn from these comparisons, especially between closely related organisms. Several genome sequences published recently indicate the value of comparisons at the genomic level.

The continued rise of Clostridium difficile infections worldwide has been accompanied by the rapid emergence of a highly virulent clone designated PCR-ribotype 027. To understand more about the evolution of this virulent clone, we made a three-way genomic and phenotypic comparison of an 'historic' non-epidemic 027 C. difficile (CD196), a recent epidemic and hypervirulent 027 (R20291) and a previously sequenced PCR-ribotype 012 strain (630).

Background Stenotrophomonas maltophilia is a nosocomial opportunistic pathogen of the Xanthomonadaceae. The organism has been isolated from both clinical and soil environments in addition to the sputum of cystic fibrosis patients and the immunocompromised. Whilst relatively distant phylogenetically, the closest sequenced relatives of S. maltophilia are the plant pathogenic xanthomonads.Results The genome of the bacteremia-associated isolate S. maltophilia K279a is 4,851,126 bp and of high G+C content. The sequence reveals an organism with a remarkable capacity for drug and heavy metal resistance. In addition to a number of genes conferring resistance to antimicrobial drugs of different classes via alternative mechanisms, nine resistance-nodulation-division (RND)-type putative antimicrobial efflux systems are present. Functional genomic analysis confirms a role in drug resistance for several of the novel RND efflux pumps. S. maltophilia possesses potentially mobile regions of DNA and encodes a number of pili and fimbriae likely to be involved in adhesion and biofilm formation that may also contribute to increased antimicrobial drug resistance.Conclusion The panoply of antimicrobial drug resistance genes and mobile genetic elements found suggests that the organism can act as a reservoir of antimicrobial drug resistance determinants in a clinical environment, which is an issue of considerable concern.

Two bacteria are featured this month, and both are at the lower end of the genome size scale. The first, Mycoplasma gallisepticum, belongs to a group of bacteria that have been studied both as important human and animal pathogens and in the pursuit of understanding the essential functions of a self-replicating minimal cell. The second, Nanoarchaeum equitans, is an obligate symbiont that only grows in co-culture with another archaeon. N. equitans seems to be the coelacanth of the microbial world — it has been assigned to a new phylum and represents a primitive form of prokaroytic life.