Distribution and abundance of tetraether lipid cyclization genes in terrestrial hot springs reflect pH
Distribution and abundance of tetraether lipid cyclization genes in terrestrial hot springs reflect pH
复制标题
DOI：
10.1111/1462-2920.16375
复制
发表时间：
2023-04-09
影响因子：
5.1
通讯作者：
Leavitt，William D. D.
中科院分区：
文献类型：
--
作者：
Blum，Laura N. N.;Colman，Daniel R. R.;Leavitt，William D. D.
许多古细菌产生跨膜脂质，使生命能够在极端环境中生存。这些类异戊二烯甘油二phytanyl甘油四醚（GDGTs）可能含有多达8个环戊基和1个环己基环，其中环化程度越高，酸性越强，温度越高或能量受限。最近，在两种磺胺菌科植物中发现了编码GDGT环合成酶的基因grsAB；然而，在这些生物和相关生物居住的环境中，这些生物的分布和丰度仍然是一个谜。为了解决这个问题，我们研究了与环境温度和pH值相关的grshomologs分布，这些分布来自地球各地的温泉，其中的序列来自宏基因组、亚转录组、单细胞和栽培基因组。土壤毒物丰度与pH呈显著负相关，与温度呈微弱正相关。古生菌基因组和宏基因组组装基因组（MAGs）携带两个或两个以上的图谱，在低pH值的泉水中更为丰富。我们还发现了12个古细菌纲，其中以热蛋白纲（Thermoproteia）为代表，其次是未培养的Korarchaeia、Bathyarchaeia和Hadarchaeia，而几个亚硝酸盐藻纲（Nitrososphaeria）编码bb30个拷贝。我们的研究结果强调了grs催化的脂质环化在高温和酸性环境中古细菌多样化中的关键作用。
Many Archaea produce membrane‐spanning lipids that enable life in extreme environments. These isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs) may contain up to eight cyclopentyl and one cyclohexyl ring, where higher degrees of cyclization are associated with more acidic, hotter or energy‐limited conditions. Recently, the genes encoding GDGT ring synthases,grsAB, were identified in two Sulfolobaceae; however, the distribution and abundance ofgrshomologs across environments inhabited by these and related organisms remain a mystery. To address this, we examined the distribution ofgrshomologs in relation to environmental temperature and pH, from thermal springs across Earth, where sequences derive from metagenomes, metatranscriptomes, single‐cell and cultivar genomes. The abundance ofgrshomologs shows a strong negative correlation to pH, but a weak positive correlation to temperature. Archaeal genomes and metagenome‐assembled genomes (MAGs) that carry two or moregrscopies are more abundant in low pH springs. We also findgrsin 12 archaeal classes, with the most representatives in Thermoproteia, followed by MAGs of the uncultured Korarchaeia, Bathyarchaeia and Hadarchaeia, while several Nitrososphaeria encodes >3 copies. Our findings highlight the key role ofgrs‐catalysed lipid cyclization in archaeal diversification across hot and acidic environments.