An arsenate-reducing and alkane-metabolizing novel bacterium, Rhizobium arsenicireducens sp. nov., isolated from arsenic-rich groundwater.
A novel arsenic (As)-resistant, arsenate-respiring, alkane-metabolizing bacterium KAs 5-22T, isolated from As-rich groundwater of West Bengal was characterized by physiological and genomic properties. Cells of strain KAs 5-22Twere Gram-stain-negative, rod-shaped, motile, and facultative anaerobic. Growth occurred at optimum of pH 6.0-7.0, temperature 30 °C. 16S rRNA gene affiliated the strain KAs 5-22Tto the genus Rhizobium showing maximum similarity (98.4 %) with the type strain of Rhizobium naphthalenivorans TSY03bTfollowed by (98.0 % similarity) Rhizobium selenitireducens B1T. The genomic G + C content was 59.4 mol%, and DNA-DNA relatedness with its closest phylogenetic neighbors was 50.2 %. Chemotaxonomy indicated UQ-10 as the major quinone; phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol as major polar lipids; C16:0, C17:0, 2-OH C10:0, 3-OH C16:0, and unresolved C18:1ɷ7C/ɷ9C as predominant fatty acids. The cells were found to reduce O2, As5+, NO3-, SO42-and Fe3+as alternate electron acceptors. The strain's ability to metabolize dodecane or other alkanes as sole carbon source using As5+as terminal electron acceptor was supported by the presence of genes encoding benzyl succinate synthase (bssA like) and molybdopterin-binding site (mopB) of As5+respiratory reductase (arrA). Differential phenotypic, chemotaxonomic, genotypic as well as physiological properties revealed that the strain KAs 5-22Tis separated from its nearest recognized Rhizobium species. On the basis of the data presented, strain KAs 5-22Tis considered to represent a novel species of the genus Rhizobium, for which the name Rhizobium arsenicireducens sp. nov. is proposed as type strain (=LMG 28795T=MTCC 12115T).
Department of Biotechnology, Indian Institute of Technology (IIT), Kharagpur, West Bengal, 721302, India.
Balaram
B
Mohapatra
Department of Biotechnology, Indian Institute of Technology (IIT), Kharagpur, West Bengal, 721302, India.
Angana
A
Sarkar
Department of Microbiology, University of Delhi South Campus (UDSC), New Delhi, 110021, India.
Swati
S
Joshi
Department of Biotechnology, Indian Institute of Technology (IIT), Kharagpur, West Bengal, 721302, India.
Atrayee
A
Chatterjee
Department of Biotechnology, National Institute of Technology (NIT), Durgapur, West Bengal, 713209, India.
Sufia Khannam
SK
Kazy
Department of Biotechnology, Indian Institute of Technology (IIT), Kharagpur, West Bengal, 721302, India.
Mrinal Kumar
MK
Maiti
Department of Microbiology, University of Delhi South Campus (UDSC), New Delhi, 110021, India.
Tulasi
T
Satyanarayana
Department of Biotechnology, Indian Institute of Technology (IIT), Kharagpur, West Bengal, 721302, India. sarpinaki@yahoo.com.
Pinaki
http://orcid.org/0000-0001-8538-2527
P
Sar
D000473:Alkanes / Q000378:metabolism*; D001149:Arsenates / Q000378:metabolism*; D001151:Arsenic / Q000032:analysis*; D005227:Fatty Acids / Q000737:chemistry; D060587:Groundwater / Q000737:chemistry / Q000382:microbiology*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012231:Rhizobium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D000473:Alkanes; D001149:Arsenates; D005227:Fatty Acids; D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D001151:Arsenic; C025657:arsenic acid
Arsenate reduction; Arsenic; Groundwater; Hydrocarbon utilization; Rhizobium arsenicireducens