Gemmatimonas groenlandica sp. nov. Is an Aerobic Anoxygenic Phototroph in the Phylum Gemmatimonadetes

• Published in: Frontiers in Microbiology
• Main Authors: Zeng, Yonghui, Nupur, Wu, Naicheng, Madsen, Anne Mette, Chen, Xihan, Gardiner, Alastair T., Kobl�ek, Michal
• Other Authors: Villum Fonden, FP7 People: Marie-Curie Actions, Grantová Agentura Ceské Republiky
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Frontiers Media SA 2021
• Subjects: Arctic; Greenland; glacier; Zackenberg
• Online Access: http://dx.doi.org/10.3389/fmicb.2020.606612; https://www.frontiersin.org/articles/10.3389/fmicb.2020.606612/full

The bacterial phylum Gemmatimonadetes contains members capable of performing bacteriochlorophyll-based phototrophy (chlorophototrophy). However, only one strain of chlorophototrophic Gemmatimonadetes bacteria (CGB) has been isolated to date, hampering our further understanding of their photoheterotrophic lifestyle and the evolution of phototrophy in CGB. By combining a culturomics strategy with a rapid screening technique for chlorophototrophs, we report the isolation of a new member of CGB, Gemmatimonas (G.) groenlandica sp. nov., from the surface water of a stream in the Zackenberg Valley in High Arctic Greenland. Distinct from the microaerophilic G. phototrophica strain AP64 T , G. groenlandica strain TET16 T is a strictly aerobic anoxygenic phototroph, lacking many oxygen-independent enzymes while possessing an expanded arsenal for coping with oxidative stresses. Its pigment composition and infra-red absorption properties are also different from G. phototrophica , indicating that it possesses a different photosystem apparatus. The complete genome sequence of G. groenlandica reveals unique and conserved features in the photosynthesis gene clusters of CGB. We further analyzed metagenome-assembled genomes of CGB obtained from soil and glacier metagenomes from Northeast Greenland, revealing a wide distribution pattern of CGB beyond the stream water investigated.