添加抗生素对新疆特殊生境微生物分离培养的影响

Effects of antibiotics on isolation and culture of microorganisms from special habitats in Xinjiang of China

摘要:

【背景】新疆特殊生境罗布泊及温宿峡谷凭借其特殊的地理位置、极端的周边自然生态环境及较少的人为活动影响，促成了其独特的微生物优质资源。【目的】为探索添加抗生素对微生物选择性分离培养的作用，优化改良新疆特殊生境微生物选择性分离培养，以减少对菌株的重复分离，还可以选择性培养更多耐受此类抗生素的微生物，发现更多生物活性产物。【方法】以高氏一号培养基为基础，添加不同浓度的β-内酰胺类抗生素阿莫西林(amoxicillin)、氨基糖苷类抗生素卡那霉素(kanamycin)、安莎大环内酯类抗生素利福平(rifampicin)、喹诺酮类抗生素诺氟沙星(norfloxacin)、酰胺醇类抗生素氯霉素(chloramphenicol)、氨基糖苷类抗生素链霉素(streptomycin)，分离新疆特殊生境罗布泊及温宿峡谷土壤样品中的微生物。【结果】添加诺氟沙星分离获得的微生物种类和数量最多，其次是卡那霉素和阿莫西林，再次是利福平和氯霉素。所选用的大多抗生素在1/10 MIC和1/15 MIC浓度时分离效果最好。罗布泊土样共分离到19株菌，分布在8个属。其中芽孢杆菌属6株、链霉菌属5株、类芽孢杆菌属3株、根瘤菌属1株、副芽孢杆菌属1株、原小单孢菌属1株、海洋杆菌属1株、野野村氏菌属1株，分离获得了5株新物种。温宿峡谷土样共分离获得73个菌株，分布在27个属。其中链霉菌属33株、鞘氨醇单胞菌属1株、假黄单胞菌属2株、假诺卡氏菌5株、假节杆菌1株、原小单孢菌2株、普里斯特氏菌属1株、植物放线孢菌1株、副球菌属1株、类芽孢杆菌属2株、类节杆菌属2株、诺卡氏菌属1株、小单胞菌属1株、红色甲基杆菌属1株、甲基杆菌属1株、副芽孢杆菌属5株、伦茨氏菌属1株、克里布所菌属2株、耐盐白蚁菌属1株、剑菌属1株、博斯氏菌属1株、节杆菌属1株、壤霉菌属2株、土壤球菌属1株、放线动孢菌属1株、异壁放线菌属1株、芽孢杆菌属1株，分离获得了14株新物种。【结论】添加诺氟沙星和卡那霉素有利于微生物的选择性分离培养，有利于发掘新菌种，本研究的开展为选择性分离培养特殊环境中的稀有微生物提供了指导。

Abstract:

[Background] The special habitats of Lop Nur and Wensu Canyon in Xinjiang of China, with their special geographical location, extreme surrounding natural ecological environment, and less influence of human activities, promote their unique high-quality microbial resources. [Objective] To explore the effect of adding antibiotics on the selective isolation and culture of microorganisms and optimize the selective isolation and culture of microorganisms in special habitats of Xinjiang to reduce the repeated isolation of strains. In addition, more microorganisms tolerant to such antibiotics could be selectively cultured to discover more bioactive products. [Methods] With Gauze’s No.1 medium as the foundation medium, different concentrations of β-lactam antibiotic amoxicillin, aminoglycoside antibiotic kanamycin, ansa macrolide antibiotic rifampin, quinolone antibiotic norfloxacin, aminool antibiotic chloramphenicol, and aminoglycoside antibiotic streptomycin were added. Microorganisms from soil samples of Lop Nur and Wensu Canyon in Xinjiang were isolated. [Results] The species and number of microorganisms isolated by norfloxacin were the highest, followed by kanamycin, amoxicillin, rifampicin, and chloramphenicol. Most antibiotics were best separated by 1/10 MIC and 1/15 MIC concentration. Nineteen strains were isolated and distributed in 8 genera. Among them, 6 strains belonged to Bacillus, 5 strains belonged to Streptomyces, 3 strains belonged to Paenibacillus, 1 strain belonged to Rhizobium, 1 strain belonged to Metabacillus, 1 strain belonged to Promicromonospora, 1 strain belonged to Pontibacter, and 1 strain belonged to Nonomuraea. Five new species were isolated. Seventy-three strains were isolated from the soil samples of Wensu Canyon and distributed in 27 genera. Among them, 33 strains belonged to Streptomyces, 1 strain belonged to Sphingomonas, 2 strains belonged to Pseudoxanthomonas, 5 strains belonged to Pseudonocardia, 1 strain belonged to Pseudarthrobacter, 2 strains belonged to Promicromonospora, 1 strain belonged to Priestia, 1 strain belonged to Plantactinospora, 1 strain belonged to Paracoccus, 2 strains belonged to Paenibacillus, 2 strains belonged to Paenarthrobacter, 1 strain belonged to Nocardia, 1 strain belonged to Micromonospora, 1 strain belonged to Methylorubrum, 1 strain belonged to Methylobacterium, 5 strains belonged to Metabacillus, 1 strain belonged to Lentzea, 2 strains belonged to Kribbella, 1 strain belonged to Isoptericola, 1 strain belonged to Ensifer, 1 strain belonged to Bosea, 1 strain belonged to Arthrobacter, 2 strains belonged to Agromyces, 1 strain belonged to Agrococcus, 1 strain belonged to Actinokineospora, 1 strain belonged to Actinoalloteichus, and 1 strain belonged to Bacillus. Fourteen new species were isolated. [Conclusion] The addition of norfloxacin and kanamycin is beneficial to the selective isolation and culture of microorganisms and the discovery of new strains. This study provides guidance for the selective isolation and culture of rare microorganisms in special environments.