高山兀鹫肠道有益菌的分离鉴定与生物学特性研究

Isolation,Identification and Biological Characteristics of Beneficial Bacteria in the Gut of Himalayan Vultures(Gyps himalayensis)

高山兀鹫(Gyps himalayensis)作为在青藏高原广泛分布的大型食腐类猛禽,对维持高原生态系统平衡和稳定具有十分重要的意义。长期以来,对于其腐食适应性机制的研究一直备受关注。为了解高山兀鹫肠道有益菌的多样性、耐药性以及抑制腐食病原菌的情况,采集野生高山兀鹫的新鲜粪便进行细菌分离培养、16S rRNA测序、生化鉴定、耐药性分析,并对耐酸性、耐胆盐性以及抑菌性等进行研究。结果共分离到64株细菌,隶属于4个属、6个种,分别是蜡样芽孢杆菌(Bacillus cereus)、地衣芽孢杆菌(Bacillus licheniformis)、简单芽孢杆菌(Bacillus simplex)、屎肠球菌(Enterococcus faecium)、表皮葡萄球菌(Staphylococcus epidermidis)和林地土壤芽孢杆菌(Solibacillus silvestris)。耐药性分析发现,这些菌株对9种~22种不等的抗菌药物表现出耐药性。其中4种潜在有益菌耐酸、耐胆盐,pH 1时,仍然能保持生长;胆盐浓度5 mg/mL时,存活率均高于40%。这4种菌株对常见肠道致病菌大肠埃希氏菌ATCC8099、肠炎沙门氏菌CMCC50041和金黄色葡萄球菌ATCC6538具有一定的抑制作用。研究结果为高山兀鹫肠道微生物抵抗腐食病原菌的深入研究奠定了基础。

Himalayan vultures(Gyps himalayensis),large scavenging raptors widely distributed in Qinghai-Tibet Plateau,are of great significance to maintain the balance and stability of the plateau ecosystem.For a long time,the research on this species’adaptive mechanism to rotten foods has attracted much attention.To understand the diversity and resistance of beneficial bacteria in the gut of Himalayan vultures and the suppression of carrion pathogens,the fresh feces from Himalayan vultures were collected for bacterial isolation,16S rRNA gene sequencing,biochemical identification,and antimicrobial resistance tests.The properties of acid resistance,bile salt resistance and common pathogenic resistance were also studied.A total of 64 strains,belonging to 4 genera and 6 species,were isolated from the fresh feces of Himalayan vultures,including Bacillus cereus,Bacillus licheniformis,Bacillus simplex,Enterococcus faecium,Staphylococcus epidermidis,Solibacillus silvestris.Drug resistance analysis was conducted on the 6 representative isolated strains,and it was found that these strains showed resistance to 9 to 22 different antimicrobials.Further analysis showed that four of the potential beneficial strains had certain acid resistance and bile salt resistance ability,and could still maintain growth when pH was 1.The survival rate was above 40%when the bile salt concentration was 5 mg/mL.These four strains have certain inhibitory ability to common intestinal pathogenic bacteria,such as Escherichia coli ATCC8099,Salmonella enteritidis CMCC50041 and Staphylococcus aureus ATCC6538.This study lays a foundation for further research on the resistance of gut microbes of Himalayan vultures to carrion pathogens.