Taxonomy and environmental microbiology of photosynthetic prokaryotes in nature

Microbial consortia majorly consisted of photosynthetic prokaryotes are frequently found in various aqueous environments in the world. The organisms that can grow by photosynthesis play an important role not only in the supply of energy from light to the consortia but also in the formation and maintenance of microbial mats or films of the consortia. However, it has not been clear how the photosynthetic prokaryotes contribute to the formation and maintenance of these consortia. The aims of this laboratory are to reveal the formation mechanism of the photosynthetic microbial consortia and the contribution of photosynthetic prokaryotes to the stabilization of them. Also, we are aiming to control the photosynthetic microbial consortia and to make use of them for the solution of energy and environmental problems.

The formation of microbial mats in hot springs

In neutral and slight alkaline hot springs, distinctive microbial consortia called microbial mats are often observed. The microbial mats often contain filamentous anoxygenic phototrophic bacteria, Chloroflexus species. These bacteria are able to move by gliding and the motility has possibly a close relation to the formation and maintenance of the microbial mats. However, it remains unsolved how the microbial mats are formed and maintained. In addition, the gliding mechanism of Chloroflexus species is not clear yet. One of our purposes is to elucidate the unknown mechanisms of the gliding motility and the effect of the motility in the mat formation.

The taxonomic rearrangement of thermophilic cyanobacteria

Various thermophilic cyanobacteria are commonly observed in the microbial mats of hot springs in addition to Chloroflexus species. These oxygenic phototrophs supply the energy from light to many other inhabitants of the microbial mats, even to Chloroflexus species, as the primary producer. In spite of the important ecological role and the phylogenetic diversity in hot springs, the taxonomic study of thermophilic cyanobacteria has made little progress partly because the classical taxonomy of cyanobacteria has been based on morphology. It is urgently necessary to establish the proper classification of thermophilic cyanobacteria. We try to accomplish the taxonomic rearrangement.

Aerobic photosynthetic bacteria newly discovered in the river

A different type of photosynthetic microbial consortia exists in the shallow bottom of the river. The river consortia are mainly composed by green algae, diatoms, and cyanobacteria as phototrophic constituents, but they also commonly include various phylotypes of aerobic photosynthetic bacteria, which are unique aerobes mainly grown by respiration but have bacteriochlorophyll a for photosynthesis even under the aerobic conditions. The reason why these aerobic photosynthetic bacteria are widely distributed in the river consortia is still unknown. To figure out their ecological role in the environments, we are planning to obtain many new isolates further from the bottom in the river and analyze their physiological and genomic properties in detail. Systematic descriptions of newly found species and genus are also intended.

Recent Publications

1. Tarhriz V, Hirose S. Fukushima S, Hejazi MA, Imhoff JF, Thiel V, Hejazi MS. (2019) Emended description of the genus Tabrizicola and the species Tabrizicola aquatica species as aerobic anoxygenic phototrophic bacteria. Antonie van Leeuwenhoek (in press)
2. Thiel V, Garcia Costas AM, Fortney NW, Martinez JN, Tank M, Roden EE, Boyd ES, Ward DM, Hanada S, Bryant DA. (2019) "Candidatus Thermonerobacter thiotrophicus," A Non-phototrophic Member of the Bacteroidetes/Chlorobi With Dissimilatory Sulfur Metabolism in Hot Spring Mat Communities. Front. Microbiol. https://doi.org/10.3389/fmicb.2018.03159
3. Suzuki S, Nakanishi S, Tamminen M, Yokokawa T, Sato-Takabe Y, Ohta K, Chou H-Y, Muziasari WI, Virta M. (2019) Occurrence of sul and tet(M) genes in bacterial community in Japanese marine aquaculture environment through the year: profile comparison with Taiwanese and Finnish aquaculture waters. Science of the total environments 669: 649-656
4. Kanno N, Matsuura K, Haruta S (2018). Different Metabolomic Responses to Carbon Starvation between Light and Dark Conditions in the Purple Photosynthetic Bacterium, Rhodopseudomonas palustris. Microbes and Environments. 33:83-88
5. Mori K, Yamaguchi K, Hanada S (2018) Sulfurovum denitrificans sp. nov., an obligately chemolithoautotrophic sulfur-oxidizing epsilonproteobacterium isolated from a hydrothermal field. International Journal of Systematic and Evolutionary Microbiology 68: 2183-2187
6. Kimura, N, Watanabe T, Suenaga H, Fujihara H, Futagami T, Goto M, Hanada S, Hirose J (2018) Pseudomonas furukawaii sp. nov., a polychlorinated biphenyldegrading bacterium isolated from biphenyl-contaminated soil in Japan. Int J Syst Evol Microbiol 68:1429-1435
7. Wasai, S., Kanno N, Matsuura K, Haruta S (2018) Increase of salt tolerance in carbon-starved cells of Rhodopseudomonas palustris depending on photosynthesis or respiration. Microorganisms 6:4
8. Nishida A, Thiel V, Nakagawa M, Ayukawa S, Yamamura M (2018). Effect of light wavelength on hot spring microbial mat biodiversity. PLoS ONE 13: e0191650.
9. Kanno, N., Matsuura K, Haruta S (2018) Different metabolomic responses to carbon starvation between light and dark conditions in the purple photosynthetic bacterium, Rhodopseudomonas palustris. Microbes Environ 33:83-88
10. Nishihara A, Haruta S, McGlynn S, Thiel V, Matsuura K (2018). Nitrogen fixation in thermophilic chemosynthetic microbial communities depending on hydrogen, sulfate, and carbon dioxide. Microbes Environ 33:10-18
11. Thiel V, Tank M, Bryant DA (2018). Diversity of chlorophototrophic bacteria in the omics era. Annual Review of Plant Biology. 69:21-49.
12. Tank, M., Thiel, V., Ward, D. M., and Bryant, D. A. (2017). �gA panoply of phototrophs: a photomicrographic overview of chlorophototrophs found in the microbial mats of alkaline siliceous hot springs in Yellowstone National Park, WY, USA,�h in Modern Topics in the Phototrophic Prokaryotes: Environmental and Applied Aspects pp 87-137
13. Orf G, Collins A, Niedzwiedzki D, Tank M, Thiel V, Kell A, Bryant DA, Montano G, Blankenship R (2017). Polymer-chlorosome nanocomposites consisting of non-native combinations of self-assembling bacteriochlorophylls. Langmuir 33:6427-6438.
14. Thiel V, Tank M, Tomsho LP, Burhans R, Gay SE, Hamilton TL, Schuster SC, Bryant DA (2017). Draft genome sequence of Anoxybacillus ayderensis strain MT-Cab (Firmicutes). Genome Announc 5:e00547-17.
15. Thiel V, Drautz-Moses DI, Purbojati RW, Schuster SC, Lindemann S, Bryant DA. (2017) Genome sequence of Prosthecochloris sp. strain HL-130-GSB, from the phylum Chlorobi. Genome Announc 0(999):e00538-17.
16. Thiel V, Huegler M, Ward DM, Bryant DA (2017). The dark side of the Mushroom Spring microbial mat : life in the shadow of chlorophototrophs. II. Functions of abundant community members based on metagenomic sequencing. Front. Microbiol. 8:943,
17. Yasutake, Y, Kusada H, Ebuchi T, Hanada S, Kamagata Y, Tamura T, Kimura K (2017) Bifunctional quorum-quenching and antibiotic-acylase MacQ forms a 170-kDa capsule-shaped molecule containing spacer polypeptides. Scientific Reports 7:8946
18. Kusada, H, Tamaki H, Kamagata Y, Hanada S, Kimura N (2017) A novel quorum-quenching N-acylhomoserine lactone acylase from Acidovorax sp. strain MR-S7 mediates antibiotic resistance. Appl Environ Microbiol 83: e00080-17
19. Nagashima KVP, Sasaki M, Hashimoto K, Takaichi S, Nagashima S, Yu L-J, Abe Y, Gotou K, Kawakami T, Takenouchi M, Shibuya Y, Yamaguchi A, Ohno T, Shen J-R, Inoue K, Madigan MT, Kimura Y, Wang-Otomo Z-Y (2017) Probing structure–function relationships in early events in photosynthesis using a chimeric photocomplex. Proc Natl Acad Sci USA; 114:10906-10911.
20. Bernstein, HC., RS McClure, V Thiel, NC Sadler, YM. Kim, WB Chrisler, et al. Indirect interspecies regulation: Transcriptional and physiological responses of a cyanobacterium to heterotrophic partnership. mSystems. 2. doi:10.1128/mSystems.00181-16 (2017).
21. Sun, L, M Toyonaga, A Ohashi, N Matsuura, DM Tourlousse, XY Meng, H Tamaki, S Hanada, R Cruz, T Yamaguchi, Y Sekiguchi. Isolation and characterization of Flexilinea flocculi gen. nov., sp. nov., a filamentous, anaerobic bacterium belonging to the class Anaerolineae in the phylum Chloroflexi. Int J Syst Evol Microbiol 66:988-996 (2016)
22. Kasuno,, M, Hi Kimura, H Yasutomo, M Torimura, D Murakami, Ye Tsukatani, S Hanada, T Matsushita, H Tao. An Evaluation of Sensor Performance for Harmful Compounds by Using Photo-Induced Electron Transfer from Photosynthetic Membranes to Electrodes. Sensors 16:438 (2016)
23. Fukushima, S, S Morohoshi, S Hanada, K Matsuura, S Haruta. Gliding motility driven by individual cell-surface movements in a multicellular filamentous bacterium Chloroflexus aggregans. FEMS Microbiol lett 8:fnw056 (2016)
24. Sun, L, M Toyonaga, A Ohashi, DM Tourlousse, N Matsuura, XY Meng, H Tamaki, S Hanada, R Cruz, T Yamaguchi, Y Sekiguchi. Lentimicrobium saccharophilum gen. nov., sp. nov., a strictly anaerobic bacterium representing a new family in the phylum Bacteroidetes, and proposal of Lentimicrobiaceae fam. nov. Int J Syst Evol Microbiol 66:2635-2642 (2016)
25. Hirose, S., K. Matsuura, and S. Haruta. Phylogenetically Diverse Aerobic Anoxygenic Phototrophic Bacteria Isolated from Epilithic Biofilms in Tama River, Japan. Microbes Environ. 31: 299-306 (2016)
26. Thiel V, JM Wood, MT Olsen, M Tank, CG Klatt, M Ward, DA Bryant. The dark side of the Mushroom Spring microbial mat: life in the shadow of chlorophototrophs. I. Microbial diversity based on 16S rRNA amplicon and metagenome sequencing. Front. Microbiol. 7:919 (2016)