Nouioui Imen, Cortés-Albayay Carlos, Neumann-Schaal Meina, Vicente Diego, Cilla Gustavo, Klenk Hans-Peter, Marimón Jose María, Ercibengoa Maria
Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, 38124 Braunschweig, Germany.
Laboratory of Microbial Complexity and Functional Ecology, Antofagasta Institute, University of Antofagasta, 1240000 Antofagasta, Chile.
Microorganisms. 2020 Oct 1;8(10):1517. doi: 10.3390/microorganisms8101517.
Strains 335427 and 234509, isolated from two 76-year-old patients with chronic pulmonary diseases, were the subject of polyphasic taxonomic studies and comparative genomic analyses for virulence factors. The 16 rRNA gene sequence similarity between strains 335427 and 234509 and their closest phylogenetic neighbors NBRC 100129 and NBRC 100374 were 99.5% and 100%, respectively. Digital DNA-DNA hybridization values between the aforementioned studied strains were well below the 70% threshold for assigning prokaryotic strains to a novel species. Strains 335427 and 234509 have genome sizes of 8.49 Mpb and 8.07 Mpb, respectively, with G + C content of 68.5%. Isolate 335427 has C, C ωc, C and C 10 methyl as major fatty acids (>15%) and mycolic acids formed of 52-54 carbon atoms. However, only C ωc was detected for isolate 234509, which had mycolic acids with 44-56 carbon. Based on phenotypic and genetic data, strains 335427 (DSM 109819 = CECT 9924) and 234509 (DSM 111366 = CECT 30129) merit recognition as novel species, which are named sp. nov. and sp. nov., respectively. All the strains studied had homologous VF-associated genes to those described in , including experimentally verified virulence genes in humans related to tuberculosis. The GHIJ (nitrate reduction pathway) and AFGOJLMK (gas vesicles) genetic maps of strains 335427, 234509, NBRC 100129 and NBRC 100374 showed the same syntenic block and raise the question of whether their functions are interlinked during the infection of the human host. However, further research is required to decipher the role of the gas vesicle in the pathogenicity mechanism of spp.
从两名患有慢性肺部疾病的76岁患者中分离出的菌株335427和234509，是多相分类学研究和毒力因子比较基因组分析的对象。菌株335427和234509与其最接近的系统发育邻居NBRC 100129和NBRC 100374之间的16 rRNA基因序列相似性分别为99.5%和100%。上述研究菌株之间的数字DNA-DNA杂交值远低于将原核菌株归为新物种的70%阈值。菌株335427和234509的基因组大小分别为8.49 Mpb和8.07 Mpb，G + C含量为68.5%。分离株335427以C、C ωc、C和C 10甲基作为主要脂肪酸（>15%），其分枝菌酸由52 - 54个碳原子组成。然而，分离株234509仅检测到C ωc，其分枝菌酸含有44 - 56个碳原子。基于表型和遗传数据，菌株335427（DSM 109819 = CECT 9924）和234509（DSM 111366 = CECT 30129）应被认可为新物种，分别命名为sp. nov.和sp. nov.。所有研究的菌株都具有与[文献中]描述的那些同源的VF相关基因，包括在人类中经实验验证的与结核病相关的毒力基因。菌株335427、234509、NBRC 100129和NBRC 100374的GHIJ（硝酸盐还原途径）和AFGOJLMK（气荚膜）遗传图谱显示出相同的同线性区域，并引发了它们的功能在人类宿主感染过程中是否相互关联的问题。然而，需要进一步研究来破译气荚膜在 spp.致病机制中的作用。
