Journal article
In-Situ Metatranscriptomic Analyses Reveal the Metabolic Flexibility of the Thermophilic Anoxygenic Photosynthetic Bacterium Chloroflexus aggregans in a Hot Spring Cyanobacteria-Dominated Microbial Mat
Microorganisms (Basel), Vol.9(3), pp.1-22
03/01/2021
DOI: 10.3390/microorganisms9030652
PMCID: PMC8004040
PMID: 33801086
Abstract
Chloroflexus aggregans is a metabolically versatile, thermophilic, anoxygenic phototrophic member of the phylum Chloroflexota (formerly Chloroflexi), which can grow photoheterotrophically, photoautotrophically, chemoheterotrophically, and chemoautotrophically. In hot spring-associated microbial mats, C. aggregans co-exists with oxygenic cyanobacteria under dynamic micro-environmental conditions. To elucidate the predominant growth modes of C. aggregans, relative transcription levels of energy metabolism- and CO2 fixation-related genes were studied in Nakabusa Hot Springs microbial mats over a diel cycle and correlated with microscale in situ measurements of O-2 and light. Metatranscriptomic analyses indicated two periods with different modes of energy metabolism of C. aggregans: (1) phototrophy around midday and (2) chemotrophy in the early morning hours. During midday, C. aggregans mainly employed photoheterotrophy when the microbial mats were hyperoxic (400-800 mu mol L-1 O-2). In the early morning hours, relative transcription peaks of genes encoding uptake hydrogenase, key enzymes for carbon fixation, respiratory complexes as well as enzymes for TCA cycle and acetate uptake suggest an aerobic chemomixotrophic lifestyle. This is the first in situ study of the versatile energy metabolism of C. aggregans based on gene transcription patterns. The results provide novel insights into the metabolic flexibility of these filamentous anoxygenic phototrophs that thrive under dynamic environmental conditions.
Details
- Title: Subtitle
- In-Situ Metatranscriptomic Analyses Reveal the Metabolic Flexibility of the Thermophilic Anoxygenic Photosynthetic Bacterium Chloroflexus aggregans in a Hot Spring Cyanobacteria-Dominated Microbial Mat
- Creators
- Shigeru Kawai - Tokyo Metropolitan UniversityJoval N. Martinez - Tokyo Metropolitan UniversityMads Lichtenberg - University of CopenhagenErik Trampe - University of CopenhagenMichael Kuhl - University of CopenhagenMarcus Tank - Tokyo Metropolitan UniversityShin Haruta - Tokyo Metropolitan UniversityArisa Nishihara - National Institute of Advanced Industrial Science and TechnologySatoshi Hanada - Tokyo Metropolitan UniversityVera Thiel - Tokyo Metropolitan University
- Resource Type
- Journal article
- Publication Details
- Microorganisms (Basel), Vol.9(3), pp.1-22
- DOI
- 10.3390/microorganisms9030652
- PMID
- 33801086
- PMCID
- PMC8004040
- NLM abbreviation
- Microorganisms
- ISSN
- 2076-2607
- eISSN
- 2076-2607
- Publisher
- Mdpi
- Number of pages
- 22
- Grant note
- Institute for Fermentation, Osaka (IFO); Institute for Fermentation (IFO) Tokyo Metropolitan University DFF-1323-00065B; DFF-8021-00308B / Independent Research Fund Denmark
- Language
- English
- Date published
- 03/01/2021
- Academic Unit
- Anesthesia
- Record Identifier
- 9984296123402771
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