Open AccessHalococcoides cellulosivorans gen. nov., sp. nov., an extremely halophilic cellulose-utilizing haloarchaeon from hypersaline lakes
Author(s) -
Dimitry Y. Sorokin,
Tatiana V. Khijniak,
Alexander G. Elcheninov,
Stepan V. Toshchakov,
N. A. Kostrikina,
Nicole J. Bale,
Jaap S. Sinninghe Damsté,
Ilya V. Kublanov
Publication year - 2019
Publication title -
international journal of systematic and evolutionary microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.925
H-Index - 173
eISSN - 1466-5034
pISSN - 1466-5026
DOI - 10.1099/ijsem.0.003312
Subject(s) - halophile , biology , rpob , 16s ribosomal rna , botany , cellobiose , microbiology and biotechnology , bacteria , cellulose , biochemistry , cellulase , genetics
An extremely halophilic euryarchaeon, strain HArcel1 T , was enriched and isolated in pure culture from the surface brines and sediments of hypersaline athalassic lakes in the Kulunda Steppe (Altai region, Russia) using amorphous cellulose as the growth substrate. The colonies of HArcel1 T are pale-orange, and form large zones of cellulose hydrolysis around them. The cells are non-motile cocci of variable size with a thin monolayer cell wall. The isolate is an obligate aerobic heterotroph capable of growth with only three substrates: various forms of insoluble cellulose, xylan and cellobiose. Strain HArcel1 T is an extremely halophilic neutrophile, growing within the salinity range from 2.5 to 5 M NaCl (optimum at 3.5-4 M). The core archaeal lipids are dominated by C20-C20 and C25-C20 dialkyl glycerol ethers, in approximately 6:1 proportion. The 16S rRNA and rpoB' gene analysis indicated that HArcel1 T forms a separate lineage within the family Haloarculaceae, order Halobacteriales, with the genera Halorhabdus and Halopricus as closest relatives. On the basis of the unique phenotypic properties and distinct phylogeny of the 16S rRNA and rpoB' genes, it is suggested that strain HArcel1 T is classified into a new genus and species Halococcoides cellulosivorans gen. nov., sp. nov. (JCM 31941 T =UNIQEM U975 T ).