摘要
      硫酸盐还原细菌，主要是脱硫弧菌，负责在猪生产废物中积极产生H2S。硫酸盐还原研究的模式物种，寻常脱硫弧菌菌株L2，以前是从猪粪中分离出来的，其特征是高异化硫酸盐还原率。低硫酸盐猪粪便中H2S形成率高的电子受体来源仍不确定。在这里，我们证明了L2菌株使用常见畜牧业补充剂的能力，包括L-赖氨酸硫酸盐、石膏和石膏板作为H2S生产的电子受体。L2菌株的基因组测序揭示了两个大质粒的存在，并预测了对各种抗菌药物和汞的耐药性，这在生理实验中得到了证实。大多数抗生素抗性基因（ARG）由位于染色体和质粒pDsulf-L2-2上的两个1类整合子携带。这些ARGs被预测会对β-内酰胺类、氨基糖苷类、林可酰胺类、磺酰胺类、氯霉素和四环素产生耐药性，可能是从各种γ-变形杆菌和厚壁菌门横向获得的。对汞的抗性可能是由同样位于染色体和pDsulf-L2-2上的两个mer操纵子实现的，并通过水平基因转移获得。第二个大质粒pDsulf-L2-1编码固氮酶、过氧化氢酶和III型分泌系统，表明该菌株与猪肠道中的肠细胞密切接触。ARGs在可移动元件上的位置使我们能够将D.vulgaris菌株L2视为一种可能的载体，在肠道微生物群和环境生物位中的微生物群落之间转移抗微生物耐药性决定因素。
Abstract
Sulphate-reducing bacteria, primarily Desulfovibrio, are responsible for the active generation of H2S in swine production waste. The model species for sulphate reduction studies, Desulfovibrio vulgaris strain L2, was previously isolated from swine manure characterized by high rates of dissimilatory sulphate reduction. The source of electron acceptors in low-sulphate swine waste for the high rate of H2S formation remains uncertain. Here, we demonstrate the ability of the L2 strain to use common animal farming supplements including L-lysine-sulphate, gypsum and gypsum plasterboards as electron acceptors for H2S production. Genome sequencing of strain L2 revealed the presence of two megaplasmids and predicted resistance to various antimicrobials and mercury, which was confirmed in physiological experiments. Most of antibiotic resistance genes (ARG) are carried by two class 1 integrons located on the chromosome and on the plasmid pDsulf-L2-2. These ARGs, predicted to confer resistance to beta-lactams, aminoglycosides, lincosamides, sulphonamides, chloramphenicol and tetracycline, were probably laterally acquired from various Gammaproteobacteria and Firmicutes. Resistance to mercury is likely enabled by two mer operons also located on the chromosome and on pDsulf-L2-2 and acquired via horizontal gene transfer. The second megaplasmid, pDsulf-L2-1, encoded nitrogenase, catalase and type III secretion system suggesting close contact of the strain with intestinal cells in the swine gut. The location of ARGs on mobile elements allows us to consider D. vulgaris strain L2 as a possible vector transferring antimicrobials resistance determinants between the gut microbiote and microbial communities in environmental biotopes.

https://www.mdpi.com/2076-2607/11/4/838