Branched GDGT production at elevated temperatures in anaerobic soil microcosm incubations

Chen, Yufei1; Zheng, Fengfeng1; Chen, Songze1; Liu, Haodong1; Phelps, Tommy J.2; Zhang, Chuanlun3

2018-03

10.1016/j.orggeochem.2017.11.015

ORGANIC GEOCHEMISTRY   影响因子和分区

0146-6380

Branched glycerol dialkyl glycerol tetraethers (bGDGTs) are unique ether-linked bacterial membrane lipids, which occur in diverse environments. Acidobacteria are considered to produce them in acidic soils and peat bogs. However, the biological source(s) of bGDGTs other than acidobacteria in alkaline soils and their response to environmental changes are obscure. We designed a 1 year incubation experiment under elevated temperature conditions (30 degrees C, 45 degrees C and 85 degrees C)in order to accelerate the growth of mesophilic and thermophilic bacteria that may potentially produce bGDGTs and to understand the mechanisms underlying the changes in bGDGT composition. The soil we selected was alkaline (pH > 8) with a small population of acidobacteria being detected using high throughput sequencing. The medium contained nutrients and organic carbon and samples were incubated under anaerobic conditions with pH of 7.5, in order to stimulate the growth of heterotrophic and anaerobic bacteria from the soil. Quantitative polymerase chain reaction (qPCR) was employed to monitor the growth status of bacteria at the beginning and the end of the experiment. The results showed multiple lines of evidence for bGDGT biosynthesis, including: (1) increased total abundance of both PL-bGDGTs (polar lipid-derived bGDGTs, "living") and CL-bGDGTs (core lipid bGDGTs, "dead") at 30 degrees C and 45 degrees C, but not 85 degrees C; (2) changes in bGDGT distribution at 30 degrees C and 45 degrees C; and (3) increased temperature inferred by the bGDGT-based proxy at an incubation temperature at 45 degrees C. Estimated turnover time of both PL-and CL-bGDGTs was 1-8 months at 30 degrees C or 45 degrees C under these laboratory conditions, which agrees with previous studies. Our study suggests that raising temperature may stimulate growth of bGDGT-producing bacteria that likely includes some anaerobic heterotrophs other than acidobacteria. (C) 2017 Elsevier Ltd. All rights reserved.

Soil bGDGTs Incubation Biological sources Bacteria Elevated temperature

SCI ; EI

英语

通讯

Shanghai Bureau of Science and Technology[13JC1405200]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:000427641300002

PERGAMON-ELSEVIER SCIENCE LTD

20181304954423

Alkalinity ; Biochemistry ; Glycerol ; Lipids ; Organic carbon ; Polymerase chain reaction ; Soils

Soils and Soil Mechanics:483.1 ; Chemistry, General:801.1 ; Biochemistry:801.2 ; Organic Compounds:804.1

GEOSCIENCES

Web of Science

1.Tongji Univ, State Key Lab Marine Geol, Shanghai 200092, Peoples R China
2.Univ Tennessee, Ctr Biotechnol, Knoxville, TN 37996 USA
3.Southern Univ Sci & Technol, Dept Ocean Sci & Engn, Shenzhen 518055, Peoples R China

Chen, Yufei,Zheng, Fengfeng,Chen, Songze,et al. Branched GDGT production at elevated temperatures in anaerobic soil microcosm incubations[J]. ORGANIC GEOCHEMISTRY,2018,117:12-21.

Chen, Yufei,Zheng, Fengfeng,Chen, Songze,Liu, Haodong,Phelps, Tommy J.,&Zhang, Chuanlun.(2018).Branched GDGT production at elevated temperatures in anaerobic soil microcosm incubations.ORGANIC GEOCHEMISTRY,117,12-21.

Chen, Yufei,et al."Branched GDGT production at elevated temperatures in anaerobic soil microcosm incubations".ORGANIC GEOCHEMISTRY 117(2018):12-21.