Yatsentyuk Svetlana, Pobolelova Julia, Gordeeva Veronika, Timofeeva Irina
Department of Biotechnology, Russian State Center for Animal Feed and Drug Standardization and Quality, 5, Zvenigorodskoe Highway, Moscow, Russia.
Vet World. 2023 Feb;16(2):272-280. doi: 10.14202/vetworld.2023.272-280. Epub 2023 Feb 14.
is a Gram-negative bacterium belonging to the family that can cause bovine histophilosis. may act as a commensal or opportunistic bacterial cattle pathogen. Comparing genomes of the pathogenic strain 2336 with the non-pathogenic preputial 129Pt isolate revealed some putative virulence factors. The study of the complete genomes of strains circulating in Russia has never been conducted before. This study aimed to identify genetic features of the strains isolated in Russia and evaluate the possibility of using strains for vaccine development.
Three strains of were isolated from different sources. Strain 188-VIEV was isolated from a vaginal swab sample of cattle with endometritis. 532-VIEV and 551-VIEV were cultured from the cryopreserved bull semen samples imported from Canada. strain ATCC 700025 provided by ATCC (American Type Culture Collection) was also used in the study. DNA extraction was performed using QIAamp DNA Mini Kit (QIAGEN, USA). The whole-genome sequencing of the four strains was performed using Illumina Miseq. The comparison of the resulting sequences with the complete genomes of 2336 and 129Pt, and detection of the resistance genes and virulence factors, was performed using the ResFinder and Virulence Factor Database web services.
The genome size of the samples varied from 1.9 to 2.3 Mb. The number of coding sequences varied from 1795 to 2256. The average sequence density was 90%. The total guanine-cytosine (GC) content was 36.8%-37.2%, which coincided with data previously obtained for . Three out of four studied strains encoded putative virulence factors such as filamentous hemagglutinin homologs, lipooligosaccharide biosynthesis proteins, and proteins involved in iron transport and utilization. The Ser83Ile substitution was identified in the DNA topoisomerase II () in strains 532-VIEV and 551-VIEV cultured from bull semen which led to resistance to fluoroquinolones. The gene ('') encoding a bifunctional aminoglycoside modification enzyme was detected in strain 551-VIEV.
Strains with virulence genes identified could be candidates for designing vaccines and potentially represent antigen sources. The results show that antibiotic-resistant can be spread with semen used for artificial insemination.
[细菌名称]是一种革兰氏阴性菌，属于[细菌所属家族名称]，可引起牛组织胞浆菌病。它可能作为共生菌或机会性牛病原体。将致病菌株2336的基因组与非致病的包皮分离株129Pt进行比较，发现了一些假定的毒力因子。此前从未对俄罗斯流行的[细菌名称]菌株的全基因组进行过研究。本研究旨在确定俄罗斯分离的[细菌名称]菌株的遗传特征，并评估使用这些菌株进行疫苗开发的可能性。
从不同来源分离出三株[细菌名称]。菌株188-VIEV从患有子宫内膜炎的牛的阴道拭子样本中分离得到。532-VIEV和551-VIEV从从加拿大进口的冷冻公牛精液样本中培养得到。美国典型培养物保藏中心（ATCC）提供的[细菌名称]菌株ATCC 700025也用于本研究。使用QIAamp DNA Mini试剂盒（美国QIAGEN公司）进行DNA提取。使用Illumina Miseq对这四株菌株进行全基因组测序。使用ResFinder和毒力因子数据库网络服务将所得序列与2336和129Pt的全基因组进行比较，并检测耐药基因和毒力因子。
样本的基因组大小在1.9至2.3 Mb之间。编码序列的数量在1795至2256之间。平均序列密度为90%。鸟嘌呤-胞嘧啶（GC）总含量为36.8%-37.2%，与先前获得的[细菌名称]数据一致。四株研究菌株中有三株编码假定的毒力因子，如丝状血凝素同源物、脂寡糖生物合成蛋白以及参与铁运输和利用的蛋白。在从公牛精液中培养的532-VIEV和551-VIEV菌株的DNA拓扑异构酶II（[酶名称]）中鉴定出Ser83Ile替换，这导致对氟喹诺酮类药物耐药。在551-VIEV菌株中检测到编码双功能氨基糖苷修饰酶的基因（[基因名称]）。
鉴定出具有毒力基因的菌株可能是设计疫苗的候选菌株，并可能代表抗原来源。结果表明，耐抗生素的[细菌名称]可通过用于人工授精的精液传播。
