Vertical variation in Vibrio community composition in Sansha Yongle Blue Hole and its ability to degrade macromolecules

• 作者: Bei Li Jiwen Liu Liang Fu Lin Chen Peng Yao Shun Zhou Xiao-Hua Zhang Xiaolei Wang Zuosheng Yang
• 来源期刊: 海洋生命科学与技术(英文)
• 学科: 农学
• 关键词: Vibrio community Vertical stratification Carbon source utilization Sansha Yongle Blue Hole
• 年，卷（期）: 2020,（1）
• 页码范围: 60-72
• 页数: 13页
• 分类号: S94

摘要

With the advantages of wide distribution,fast growth,and broad metabolic spectrum to organic carbon compounds,Vibrio may play an important role in organic carbon cycling.However,the ecological roles of Vibrio in many marine environments have not been explored.Here,the world's deepest'blue hole',the Sansha Yongle Blue Hole(SYBH)in the South China Sea,which is a geographically semi-enclosed environment featuring unique chemical characters,was investigated.The abundance,diversity and carbon source utilization capability of Vibrio were studied by quantification and high-throughput sequencing of Vibrio specific 16S rRNA genes and cultivation methods.The abundance of Vibrio in water column of the SYBH ranged from 3.78×10^4 to 7.35×10^616S rRNA gene copies L_1.Free-living Vibrio was more abundant than particle-associated Vibrio(~1.20×10^6 versus-2.68×10^5 gene copies L_1),indicating that Vibrio prefers a free-living life style.The Vibrio assemblages showed clear vertical stratification and could be divided into three groups:aerobic-transition,middle anaerobic and bottom anaerobic zones.Dissolved oxygen(DO),temperature,pH and salinity were the main environmental factors affecting the abundance and community composition.Cultivated Vibrio demonstrated a degrading capability to various macromolecular substrates,including starch,Tween 20/40/80,DNA,gelatin,alginate,casein,chitin,lecithin,K-carrageenan,mannan,xylan and hyaluronic acid.This suggests that Vibrio could produce a variety of highly active extracellular enzymes.Our study provides new insights into the distribution pattern and possible role in carbon cycle of Vibrio in the unique environment of a"blue hole'.