Staphylococcus simiae

Abstract: Staphylococcus aureus (S. aureus) is the key organism for food poisoning due to massive production of heat stable exotoxins. The current study was attempted to investigate the effect of Mr. Trivedi’s biofield treatment on S. aureus. S. aureus (ATCC 25923) was divided into two parts, Group (Gr.) I: control and Gr. II: treatment. After biofield treatment, Gr. II was further subdivided into two parts, Gr. IIA and Gr. IIB. Gr. IIA was analyzed on day 10, while Gr. IIB was stored and analyzed on day 159 after revival (Study I). The revived sample (Gr. IIB) were retreated on day 159 (Study II), and divided into three separate tubes. Tube 1 was analyzed on day 5, likewise, tube 2 and 3 were analyzed on day 10 and 15, respectively. All the experimental parameters were studied using automated MicroScan Walk-Away® system. The 16S rDNA sequencing was carried out in Gr. IIA sample to correlate the phylogenetic relationship of S. aureus with other bacterial species. The antimicrobial susceptibility and minimum inhibitory concentration showed significant alteration i.e. 92.86% and 90.00% respectively in treated cells of S. aureus as compared to control. The biochemical reactions also showed the significant (35.71%) alteration in treated sample with respect to control. The biotype number and microbial species were substantially changed in Gr. IIA (767177; Staphylococcus cohnii subsp. urealyticum) on day 10, while only the biotype numbers were changed in rest of the treated samples as compared to control (307016; S. aureus). The 16S rDNA analysis showed that the identified strain in this experiment was S. aureus (GenBank Accession No.: L37597) after biofield treatment. However, the nearest homolog genus-species was found as Staphylococcus simiae (GenBank Accession No.: DQ127902). These results suggested that biofield treatment has a significant impact on S. aureus in lyophilized as well as revived state.

Abstract: We developed a method to predict bacterial pathogenicity against mammals by measuring bacterial virulence in silkworms at 37°C, human body temperature. One hundred and twenty-two strains of bacteria were isolated from the intestines of fish and shellfish and tested for their virulence against silkworms. Overnight cultures of 50 strains killed at least 50% of the silkworms when injected into the hemolymph. Of 10 strains that showed the most potent pathogenicity against silkworms, 8 also killed mice within 4 days after injection, including Staphylococcus simiae and Staphylococcus pasteuri, neither of which was previously reported to be pathogenic against mammals. These findings suggest that bacterial pathogenicity against mammals can be predicted based on measurements of silkworm-killing activity.

Abstract: Eight coagulase-negative, oxidase-negative and novobiocin-susceptible staphylococcal strains were isolated from the gastrointestinal tract of South American squirrel monkeys (Saimiri sciureus L.). These strains were differentiated from known staphylococcal species on the basis of 16S rRNA gene and hsp60 gene sequencing, and from the most closely related species using DNA-DNA hybridization, ribotyping, whole cell protein profiles and biotyping. Phylogenetic analysis based on 16S rRNA gene sequence confirmed that these strains are members of the Staphylococcus aureus species group (99 % similarity) but are similar in biochemical characteristics to Staphylococcus piscifermentans from which they can be phenotypically distinguished by resistance to polymyxin B, acid production from D-mannitol, negative hydrolysis of esculin and DNA, and negative production of beta-glucosidase. Based on the results, a novel species of the genus Staphylococcus is described, for which the name Staphylococcus simiae sp. nov. is proposed. The type strain has been deposited in the Czech Collection of Microorganisms under accession number CCM 7213T (= LMG 22723T).

Abstract: Staphylococcus belongs to the Gram-positive low G + C content group of the Firmicutes division of bacteria. Staphylococcus aureus is an important human and veterinary pathogen that causes a broad spectrum of diseases, and has developed important multidrug resistant forms such as methicillin-resistant S. aureus (MRSA). Staphylococcus simiae was isolated from South American squirrel monkeys in 2000, and is a coagulase-negative bacterium, closely related, and possibly the sister group, to S. aureus. Comparative genomic analyses of closely related bacteria with different phenotypes can provide information relevant to understanding adaptation to host environment and mechanisms of pathogenicity. We determined a Roche/454 draft genome sequence for S. simiae and included it in comparative genomic analyses with 11 other Staphylococcus species including S. aureus. A genome based phylogeny of the genus confirms that S. simiae is the sister group to S. aureus and indicates that the most basal Staphylococcus lineage is Staphylococcus pseudintermedius, followed by Staphylococcus carnosus. Given the primary niche of these two latter taxa, compared to the other species in the genus, this phylogeny suggests that human adaptation evolved after the split of S. carnosus. The two coagulase-positive species (S. aureus and S. pseudintermedius) are not phylogenetically closest but share many virulence factors exclusively, suggesting that these genes were acquired by horizontal transfer. Enrichment in genes related to mobile elements such as prophage in S. aureus relative to S. simiae suggests that pathogenesis in the S. aureus group has developed by gene gain through horizontal transfer, after the split of S. aureus and S. simiae from their common ancestor. Comparative genomic analyses across 12 Staphylococcus species provide hypotheses about lineages in which human adaptation has taken place and contributions of horizontal transfer in pathogenesis.