Natural Sciences Department, Université du Québec en Outaouais, 58 Rue Principale, Ripon, QC, J0V 1V0, Canada.
Universidad Nacional de Colombia Sede Medellín, Cra. 65 #59a-110, Medellín, Colombia.
Antonie Van Leeuwenhoek. 2023 Nov;116(11):1171-1184. doi: 10.1007/s10482-023-01856-7. Epub 2023 Sep 8.
Mangroves are a challenging ecosystem for the microorganisms that inhabit them, considering they are subjected to stressful conditions such as high and fluctuating salinity. Metagenomic analysis of mangrove soils under contrasting salinity conditions was performed at the mouth of the Ranchera River to the Caribbean Sea in La Guajira, Colombia, using shotgun sequencing and the Illumina Hiseq 2500 platform. Functional gene analysis demonstrated that salinity could influence the abundance of microbial genes involved in osmoprotectant transport, DNA repair, heat shock proteins (HSP), and Quorum Sensing, among others. In total, 135 genes were discovered to be linked to 12 pathways. Thirty-four genes out of 10 pathways had statistical differences for a p-value and FDR < 0.05. UvrA and uvrB (nucleotide excision repair), groEL (HSP), and secA (bacterial secretion system) genes were the most abundant and were enriched by high salinity. The results of this study showed the prevalence of diverse genetic mechanisms that bacteria use as a response to survive in the challenging mangrove, as well as the presence of various genes that are recruited in order to maintain bacterial homeostasis under conditions of high salinity.
红树林是一个具有挑战性的生态系统，栖息其中的微生物也面临着高盐度和波动等压力条件。本研究对哥伦比亚瓜希拉拉腊雷拉河入海口到加勒比海的红树林土壤进行了宏基因组分析，采用鸟枪法测序和 Illumina Hiseq 2500 平台，分析了不同盐度条件下的微生物群落。功能基因分析表明，盐度可能会影响与渗透保护剂转运、DNA 修复、热休克蛋白 (HSP) 和群体感应等相关的微生物基因的丰度。共发现 135 个与 12 条途径相关的基因。有 34 个基因在 10 条途径中具有统计学差异，p 值和 FDR<0.05。核苷酸切除修复中的 UvrA 和 uvrB、HSP 中的 groEL 和细菌分泌系统中的 secA 等基因最为丰富，并被高盐度所富集。本研究结果表明，细菌在红树林这一极具挑战性的环境中生存时，存在多种遗传机制，并且在高盐度条件下，为了维持细菌内稳态，还会招募各种基因。
