Xinfangfangia pollutisoli sp. nov., Isolated from Clopyralid-Contaminated Soil.

Abstract

With the aim of isolating clopyralid-degrading bacterial species for potential bioremediation, a pale-yellow, Gram-negative, rod-shaped, and non-motile designated as Clo-40T was isolated from soil which was about 10years use of clopyralid in Zaozhuang city, Shandong province. Growth occurred within the ranges from 10 to 40°C and 0-2.5% (w/v) NaCl. Strain could completely degrade 50mg/L clopyralid within 2days after induction and formed 3, 6-hydroxypicolinic acid, a major clopyralid metabolite, hydrolyze esculin, and reduce nitrates to nitrites, but could not hydrolyze gelatin. Based on phylogenetic analysis, strain clustered within the genus Xinfangfangia clade and branched with Xinfangfangia humi IMT-291T (97.6%) and Xinfangfangia soli ZQBWT (96.9%). Genome sequencing revealed a genome size of 4.41 Mbp and G + C content of 67.3%. The average nucleotide ANI values of strain with respect to X. humi IMT-291T and X. soli ZQBWT were 77.5% and 76.9%, respectively. The DDH estimated values between strain Clo-40T and X. humi IMT-291T and X. soli ZQBWT were 20.5% and 20.0%, respectively. The predominant fatty acids (> 5% of the total fatty acids) were C18:1 w7c (42.9%), C16:0 (28.8%), C17:0 cyclo (13.0%), and C14:0 (7.0%). The major polar lipids were identified as phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid, unidentified glycolipid, and unidentified lipids. The predominant respiratory quinone was Q-10. Based on data from phenotypic, chemotaxonomic, and genotypic analyses in this study, strain Clo-40T represent a novel species in the genus of Xinfangfangia, for which the name Xinfangfangia pollutisoli sp. nov. is proposed. The type strain is Clo-40T (= KCTC 92089T = GDMCC 1.2845T).