Mucilaginibacter composti sp. nov., with ginsenoside converting activity, isolated from compost

Abstract

The Gram-negative, strictly aerobic, non-motile, non-spore-forming, rod shaped bacterial strain designated TR6-03(T) was isolated from compost, and its taxonomic position was investigated by using a polyphasic approach. Strain TR6-03(T) grew at 4-42°C and at pH 6.0-8.0 on R2A and nutrient agar without NaCl supplement. Strain TR6-03(T) had β-glucosidase activity, which was responsible for its ability to transform ginsenoside Re (one of the dominant active components of ginseng) to Rg(2). On the basis of 16S rRNA gene sequence similarity, strain TR6-03(T) was shown to belong to the family Sphingobacteriaceae and to be related to Mucilaginibacter lappiensis ANJLI2(T) (96.3% sequence similarity), M. dorajii FR-f4(T) (96.1%), and M. rigui WPCB133(T) (94.1%). The G+C content of the genomic DNA was 45.6%. The predominant respiratory quinone was MK-7 and the major fatty acids were summed feature 3 (comprising C(16:1) ω7c and/or iso-C(15:0) 20H), iso-C(16:0) and iso-C(17:0) 3OH. DNA and chemotaxonomic data supported the affiliation of strain TR6-03(T) to the genus Mucilaginibacter. Strain TR6-03(T) could be differentiated genotypically and phenotypically from the recognized species of the genus Mucilaginibacter. The isolate therefore represents a novel species, for which the name Mucilaginibacter composti sp. nov. is proposed, with the type strain TR6-03(T) (=KACC 14956(T) = KCTC 12642(T) =LMG 23497(T)).

Mucilaginibacter pocheonensis sp. nov., with ginsenoside-converting activity, isolated from soil of a ginseng-cultivating field

“…Among them, a strain designated as Gsoil 032 T isolated from soil of a ginseng field in Pocheon Province (South Korea) which could convert ginsenoside Rb 1 became the subject of a taxonomic investigation. Biotransformation of ginsenoside (deglycosylation) can be achieved by hydrolysing and removing sugar moieties from the major ginsenosides such as Rb 1 , Rb 2 , Rc and Rd using bacterial and fungal strains Choi et al, 2011;Cui et al, 2011;Quan et al, 2011;Chang et al, 2014) because the efficacy of deglycosylated ginsenosides such as Rg 3 , Rh 2 , F 2 and compound K (C-K) increases †These authors contributed equally to this work.…”

Identification and Characterization of a Ginsenoside-Transforming β-Glucosidase from Pseudonocardia sp. Gsoil 1536 and Its Application for Enhanced Production of Minor Ginsenoside Rg2(S)

“…10). The research team behind this paper searched the ginsenoside hydrolyzing bacteria [27], [56], [57] and constructed several ginsenoside-hydrolyzing recombinant enzymes [28], [29], [30], [31], [46], [48], [58], [59] by surveying the ginsenoside-hydrolyzing enzymes. However, these enzymes are not applicable or are not active in transforming the Re.…”

“…Another method of obtaining Rg 2 ( S ) is to use microbes or enzymatic processes. One example is Mucilaginibacter composti TR6-03 T , which has β-glucosidase activity and showed an ability to convert ginsenoside Re into Rg 2 ( S ) [27]. Although several ginsenoside hydrolyzing recombinant enzymes have been constructed, the majority of these have hydrolysis ability with respect to protopanaxadiol type ginsenosides (i.e.…”

Mucilaginibacter agri sp. nov. and Mucilaginibacter humi sp. nov., isolated from soil

“…The genus Mucilaginibacter , a member of the family Sphingobacteriaceae , was first proposed in 2007, with Mucilaginibacter paludis as the type species isolated from an acidic sphagnum peat bog [1]. At the time of writing, the genus Mucilaginibacter comprises 59 validly published species that have been isolated from diverse environmental habitats such as soil [2, 3], freshwater [4, 5], rice straw [6], compost [7], plant [8], rotten wood [9] and moss [10]. Members of the genus Mucilaginibacter generally feature Gram-negative, oxidase-positive, non-motile rods containing menaquinone-7 (MK-7) and iso-C 15:0 , iso-C 17:0 3-OH and summed feature 3 (C 16:1 ω 7c and/or C 16:1 ω 6c ) as major respiratory quinone and cellular fatty acids, respectively [1–10].…”