naa a22 4500 510754716 CHVBK 20180411083118.0 cr unu---uuuuu 180411e20130201xx s 000 0 eng 10.1007/s13131-013-0275-7 doi (NATIONALLICENCE)springer-10.1007/s13131-013-0275-7 Key genes expression of reductive tricarboxylic acid cycle from deep-sea hydrothermal chemolithoautotrophic Caminibacter profundus in response to salinity, pH and O2 [Elektronische Daten] [Peiqing He, Yan Liu, Wenjuan Yue, Xiaohang Huang] CO2 fixation pathway of Caminibacter profundus, a chemolithoautotrophic ɛ-Proteobacteria from deep-sea hydrothermal vent, was determined and characterized by genetic and enzymatic analyses. Gene expression of key enzymes for CO2 fixation in response to salinity, pH and O2 inMedium829 were also investigated. The results demonstrate that C. profundus contained aclB, porA and oorA, the genes encoding key enzymes of reductive tricarboxylic acid (rTCA) cycle. However, genes fragments of cbbL and cbbM encoding key enzyme of Calvin cycle were not recovered. Key enzymatic activities of ATP citrate lyase (ACL), pyruvate: ferredoxin oxidoreductase (POR) and 2-oxoglutarate: ferredoxin oxidoreductase (OOR) were also present in C. profundus. The combination of genetic and enzymatic analyses confirm that C. profundus adopted rTCA cycle for carbon assimilation. The results of aclB and oorA relative expressions of C. profundus demonstrate that the ranges of environmental factors for high genes expression were sea salt 3.0%-5.0% (optimum 3.0%), pH 5.0-6.5(optimum pH 6.5), anaerobic tomicroaerobic conditions (optimum1.0% O2). Gene expression patterns under different conditions show similar patterns with bacterial growth, revealing that key rTCA cycle genes provided molecular basis for bacterial growth and propagation. Our results suggest that C. profundus could regulate key genes of rTCA cycle for carbon assimilation and energy metabolism in response to environmental fluctuations in hydrothermal vent. The Chinese Society of Oceanography and Springer-Verlag Berlin Heidelberg, 2013 Caminibacter profundus nationallicence reductive tricarboxylic acid (rTCA) cycle nationallicence ATP citrate lyase nationallicence pyruvate: ferredoxin oxidoreductase nationallicence 2-oxoglutarate: ferredoxin oxidoreductase nationallicence hydrothermal vent nationallicence He Peiqing Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut Liu Yan Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut Yue Wenjuan Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut Huang Xiaohang Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut Acta Oceanologica Sinica The Chinese Society of Oceanography 32/2(2013-02-01), 35-41 0253-505X 32:2<35 2013 32 13131 https://doi.org/10.1007/s13131-013-0275-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s13131-013-0275-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- He Peiqing Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut NATIONALLICENCE 700 1- Liu Yan Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut NATIONALLICENCE 700 1- Yue Wenjuan Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut NATIONALLICENCE 700 1- Huang Xiaohang Key Laboratory of Marine Bioactive Substance, State Oceanic Administration, 266061, Qingdao, China aut NATIONALLICENCE 773 0- Acta Oceanologica Sinica The Chinese Society of Oceanography 32/2(2013-02-01), 35-41 0253-505X 32:2<35 2013 32 13131 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer