Phylogenetic distribution of extracellular guanyl-preferring ribonucleases renews taxonomic status of two Bacillus strains

The Journal of General and Applied Microbiology

Vera Ulyanova²  Elena Dudkina²  Olga Ilinskaya²  Raihan Shah Mahmud²  Eugen Domann¹  Valentina Vershinina² 

[1] Institute for Medical Microbiology, German Center of Infection Research (DZIF), Justus-Liebig-University;Institute of Fundamental Medicine and Biology, Kazan Federal University

关键词: Bacillus altitudinis;    Bacillus pumilus;    barnase;    extracellular ribonuclease;    phylogeny;    rpoB;    taxonomy revision;    16S rRNA gene;   

DOI  :  10.2323/jgam.2016.02.005

学科分类：微生物学和免疫学

来源: Applied Microbiology, Molecular and Cellulrar Biosciences Research Foundation

【 摘 要 】

The potential of microbial ribonucleases as promising antitumor and antiviral agents, determines today’s directions of their study. One direction is connected with biodiversity of RNases. We have analyzed completed and drafted Bacillus genomes deposited in GenBank for the presence of coding regions similar to the gene of an extracellular guanyl-preferring RNase of Bacillus amyloliquefaciens (barnase). Orthologues of the barnase gene were detected in 9 species out of 83. All of these belong to “B. subtilis” group within the genus. B. subtilis itself, as well as some other species within this group, lack such types of RNases. RNases similar to barnase were also found in species of “B. cereus” group as a part of plasmid-encoded S-layer toxins. It was also found that taxonomic states of culture collection strains, which were initially described based on a limited set of phenotypic characteristics, can be misleading and need to be confirmed. Using several approaches such as matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), sequencing of genes for 16S ribosomal RNA and RNA polymerase subunit beta followed by reconstruction of phylogenetic trees, we have re-identified two RNase-secreting Bacillus strains: B. thuringiensis B-388 which should be assigned as B. altitudinis B388 and B. intermedius 7P which should be renamed as B. pumilus 7P. Therefore, small secreted guanyl-preferring RNases are the feature of “B. subtilis” group only, which is characterized by distinctive lifestyle and adaptation strategies to environment.

【 授权许可】

Unknown