Gemmatirosa adaptations to arid and low soil organic carbon conditions worldwide
Yuanyuan Bao,
Tadeo Sáez-Sandino,
Youzhi Feng,
Xuebin Yan,
Shiying He,
Shilun Feng,
Ruirui Chen,
Hui Guo,
Manuel Delgado-Baquerizo
Affiliations
Yuanyuan Bao
Jiangsu Co-innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, PR China
Tadeo Sáez-Sandino
Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales, Australia; Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
Youzhi Feng
Jiangsu Co-innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, PR China; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing 210095, PR China; Corresponding authors.
Xuebin Yan
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, PR China
Shiying He
Key Laboratory of Agro-Environment in Downstream of Yangtze Plain, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, PR China
Shilun Feng
Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, PR China
Ruirui Chen
Jiangsu Co-innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, PR China
Hui Guo
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, PR China; Corresponding authors.
Manuel Delgado-Baquerizo
Laboratorio de Biodiversidad y Funcionamiento Ecosistémico, Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Av. Reina Mercedes 10, E-41012 Sevilla, Spain; Corresponding authors.
Aridity and warming accelerate soil organic carbon (SOC) loss, thereby compromising essential functions of soil health, such as nutrient retention and microbial diversity. However, the mechanisms by which microbes adapt to arid and low SOC conditions remain poorly understood. Here, using data from an 8-y field-scale manipulation experiment, we found that the largely undescribed Gemmatimonadetes could be among the well-adapted bacterial taxa for thriving under low SOC content and arid ecosystems. Their enhanced ability to tolerate drought stress—mediated by metabolic pathways for the synthesis of osmolytes (e.g., glycine, betaine, choline, ectoine, and histidine)—and their capacity to acquire carbon resource through glycoside hydrolase genes involved in organic matter decomposition (41.6 % and 11.8 % higher than those in the total bacterial community, respectively), could explain this pattern. Further analyses based on a global-scale standardized field survey covering all continents and major ecosystem types further confirmed that Gemmatimonadetes—and, at a finer resolution, Gemmatirosa—predominated in arid (with a peak relative abundance of Gemmatimonadetes reaching 3.8 % in dry grasslands) and warm regions (peaking at 4.5 % in Africa) of the planet, where the SOC content is low. Our work provides new insights into how a largely neglected microbial group, such as Gemmatimonadetes/Gemmatirosa, can adapt to increasing environmental stress in arid and low-carbon environments in a changing world.
