生物技术通报 ›› 2024, Vol. 40 ›› Issue (7): 285-298.doi: 10.13560/j.cnki.biotech.bull.1985.2023-1219

• 研究报告 • 上一篇    下一篇

柴达木盆地昆特依盐湖可培养嗜盐细菌多样性研究

马想蓉(), 马欣, 陈胤勋, 龙启福, 王嵘, 邢江娃()   

  1. 青海大学医学部基础医学研究中心, 西宁 810016
  • 收稿日期:2023-12-29 出版日期:2024-07-26 发布日期:2024-05-24
  • 通讯作者: 邢江娃,女,博士,副教授,研究方向:特殊环境微生物学;E-mail: xingjiangwa66@163.com
  • 作者简介:马想蓉,女,硕士研究生,研究方向:特殊环境微生物学;E-mail: 3480177451@qq.com
  • 基金资助:
    人社部2021年度高层次留学人才回国资助项目;青海大学青年科研基金(2022-QYY-15);青海大学医学部中青年科研基金(2022-kyt-1)

Diversity of Culturable Halophilic Bacteria in the Chloride Type Kunteyi Salt Lake in the Qaidam Basin

MA Xiang-rong(), MA Xin, CHEN Yin-xun, LONG Qi-fu, WANG Rong, XING Jiang-wa()   

  1. Research Center of Basic Medical Sciences, Medical College, Qinghai University, Xining 810016
  • Received:2023-12-29 Published:2024-07-26 Online:2024-05-24

摘要:

【目的】 探究不同富集时间、培养盐度、稀释梯度、培养基等对氯化物型昆特依高盐盐湖可培养嗜盐细菌多样性的影响,确定嗜盐细菌的最佳分离培养条件,挖掘更多的环境嗜盐细菌资源。【方法】 从昆特依盐湖中采集水泥混合样本,选取7种培养基和10%、18% NaCl两个盐度,采用富集培养法、平板稀释涂布法和平板分区划线法分离嗜盐菌;通过16S rRNA基因测序与BLAST序列比对确定菌株系统分类学地位。同时采用免培养Illumina MiSeq高通量测序技术分析昆特依盐湖细菌群落结构多样性特征。【结果】 免培养昆特依盐湖样本中共鉴定到细菌39门64纲101目219科703属,其中假单胞菌门(Pseudomonadota)、厚壁菌门(Bacillota)、拟杆菌门(Bacteroidota)和放线菌门(Actinomycetota)为主要的优势菌门。根据菌落的大小、形态、颜色、光泽度、透明度、质地、隆起状态和边缘特征等,共分离出436株嗜盐菌,隶属于3门3纲6目9科28属77种,其中16株可能为潜在新种。3门为厚壁菌门(Bacillota)、假单胞菌门(Pseudomonadota)和放线菌门(Actinomycetota),且均为免培养测序结果中的优势菌门。在属水平上,芽孢杆菌属(Bacillus)、盐单胞菌属(Halomonas)、喜盐芽孢杆菌属(Halobacillus)、枝芽孢菌属(Virgibacillus)和卤水杆菌属(Salicola)为优势菌属。肿块芽孢杆菌属(Tuberibacillus)、越南蔷薇菌属(Rossellomorea)和谷氨酸杆菌属(Glutamicibacter)是首次从盐湖中分离得到。18% NaCl分离得到的菌株数量明显少于10% NaCl,且多样性较低,芽孢乳杆菌科(Sporolactobacillaceae)是该条件下分出的特有菌科。7种培养基中,1/2 RCA培养基分离效果最好。最佳富集培养时间为0、7和60 d,最佳样品稀释梯度为10-2和10-3【结论】 从昆特依盐湖中共分离出嗜盐细菌3门3纲6目9科28属77种。应用多种培养基,设置不同盐度、富集培养时间和稀释梯度等可显著提升可培养嗜盐菌的多样性。

关键词: 嗜盐细菌, 生物多样性, 氯化物型盐湖, 分离培养基, 富集培养, 梯度稀释, 高通量测序

Abstract:

【Objective】 To explore the effects of different enrichment time, culture salinity, dilution gradient and medium on the diversity of culturable halophilic bacteria in chloride type Kunteyi high salt lake, to determine the best isolation and culture conditions for halophilic bacteria, and to explore more resources of environmental halophilic bacteria. 【Method】 The mixed water and mud samples were collected from Kunteyi Salt Lake, and 7 media with 2 salinities of 10% and 18% NaCl were selected to isolate the halophilic bacteria by enrichment culture, plate dilution coating and plate zonal delineation methods. The phylogenetic status of the strains was determined by 16S rRNA gene sequencing and BLAST sequence comparison. At the same time, culture-free Illumina MiSeq high-throughput sequencing technology was used to analyze the bacterial community structure diversity in Kunteyi Salt Lake. 【Result】 A total of 39 phyla, 64 classes, 101 orders, 219 families and 703 genera of bacteria were identified in the culture-free samples collected from Kunteyi Salt Lake. Among them, Pseudomonadota, Bacillota, Bacteroidota and Actinomycetota were the main dominant phyla. According to the size, shape, color, gloss, transparency, texture, uplift status, and marginal characteristics of the colonies, 436 strains of halophilic bacteria were isolated, belonging to 3 phyla, 3 classes, 6 orders, 9 families, 28 genera and 77 species, among which 16 strains were potential new species. The three phyla were Bacillota, Pseudomonadota and Actinomycetota, all of which were the dominant phyla in the culture-free results. At the genus level, Bacillus, Halomonas, Halobacillus, Virgibacillus and Salicola were the dominant genera. Tuberibacillus, Rossellomorea and Glutamicibacter were isolated from the salt lake for the first time. The number of strains isolated by 18% NaCl was significantly lower than that by 10% NaCl, and the diversity was low. Sporolactobacillaceae was the unique bacteriaceae isolated under this condition. Among the 7 media, 1/2 RCA medium had the best isolation results. The optimal enrichment time was 0, 7 and 60 d, and the optimal sample dilution gradients were 10-2 and 10-3. 【Conclusion】 There were 3 phyla, 3 classes, 6 orders, 9 families, 28 genera and 77 species of halophilic bacteria isolated from Kunteyi Salt Lake. The diversity of culturable halophilic bacteria could be significantly improved by using various culture media and different salinities, enrichment culture time and dilution gradients.

Key words: halophilic bacteria, biodiversity, chloride type salt lake, isolation medium, enrichment culture, gradient dilution, high-throughput sequencing