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

Abstract

A Gram-reaction-negative, aerobic, heterotrophic, non-motile, non-spore-forming, rod-shaped bacterial strain, designated Gsoil 032 T , was isolated from soil of a ginseng field in Pocheon Province, South Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain Gsoil 032 T grew at 10-42 C and at pH 5.0-10.0 on R2A agar medium. StrainGsoil 032 T possessed b-glucosidase activity, which was responsible for its ability to transform ginsenoside Rb 1 (one of the dominant active components of ginseng) to compound K. On the basis of 16S rRNA gene sequence similarity, strain Gsoil 032 T was shown to belong to the family Sphingobacteriaceae and to be related to Mucilaginibacter sabulilitoris SMS-12 T (97.6 % sequence similarity) and Mucilaginibacter lappiensis ANJLI2 T (97.1 %) The G+C content of the genomic DNA was 44.4 mol%. The predominant respiratory quinone was menaquinone MK-7 and the major fatty acids were summed feature 3 (comprising C 16 : 1 !6c and/or C 16 : 1 !7c), iso-C 15 : 0 and iso-C 17 : 0 3-OH. The major polar lipid detected was phosphatidylethanolamine, while the minor polar lipids were various unidentified aminophospholipids, unidentified phospholipids and unidentified polar lipids.

Mucilaginibacter inviolabilis sp. nov., isolated from the phycosphere of Haematococcus lacustris NIES 144 culture

“…Hydrolysis of lipids, carboxymethylcellulose, starch and skimmed milk was tested according to the method of Smibert and Krieg [39]. Antibiotic sensitivity was tested on R2A agar plates using the Kirby-Bauer disc diffusion method [40] with antibiotic discs including the followings (μg per disc): amikacin (30), ampicillin (10), amoxicillin (10), cefadroxil (30), cefoperazone (75), ceftazidime (30), ceftriaxone (30), chloramphenicol (30), ciprofloxacin (5), cloxacillin (1), erythromycin (15), gentamicin (10), nalidixic acid (10), netillin (30), nitrofurantoin (300), norfloxacin (10), penicillin (10), tobramycin (10) and vancomycin (30).…”

“…At the time of writing, the genus comprises 64 species with validly published names (www.bacterio.net/muciliginibacter.html), which have been isolated from various ecological niches such as tundra soil, phyllosphere, peatlands and Antarctic soil [2–5]. Some Mucilaginibacter strains have been reported to produce exopolysaccharides [6], to degrade cellulose and hemicellulose [7, 8], to degrade pectin, xylan, and laminarin [9], and have potential application in the production of pharmaceutically active minor ginsenosides [10]. Members of this genus are characterized as Gram-stain-negative, non-motile, rod-shaped, non-spore-forming bacteria [1].…”

“…The optimum temperature for growth was determined at4,10,15,20,25,30,32,35,40 and 60 °C. Salt tolerance was tested by using R2A broth media supplemented with different NaCl concentrations [0-7 % (w/v) (at 1.0 % intervals)].…”

Tình Hình Nghiên Cứu Phát Hiện Các Loài Vi Khuẩn Mới Trong Đất Trồng Nhân Sâm (Panax L.) Trên Thế Giới

“…Ngành (số loài) Tài liệu tham khảo 1 Proteobacteria (48) Park et al, 2005;Yang et al, 2005;Kim et al, 2006a;Kim et al, 2006b;Lee et al, 2006;Kim et al, 2007a;Weon et al, 2007;Yoo et al, 2007a;Yoo et al, 2007b;Yoon et al, 2007a;Jung et al, 2008;Lee et al, 2008a;Lee et al, 2008b;Weon et al, 2008;Jung et al, 2009;Kim et al, 2009a;Ten et al, 2009a;Ten et al, 2009b;Bui et al, 2010;Im et al, 2010a;Im et al, 2010b;Kim et al, 2010a;Liu et al, 2010;Srinivasan et al, 2010a;Srinivasan et al, 2010b;Srinivasan et al, 2010c;Yi et al, 2010;Jung et al, 2011;Kim et al, 2011a;Wang et al, 2011a;Wang et al, 2012;Kim et al, 2013a;Ahn et al, 2015a;Cheng et al, 2015;Farh Mel et al, 2015;Nguyen et al, 2015a;Nguyen et al, 2015b;Singh et al, 2015a;Siddiqi & Im, 2016a;Zhang et al, 2016;Zhao et al, 2016;Siddiqi & Im, 2016b.…”

“…1 R2A Proteose peptone -0,5; casamino acids -0,5; cao nấm men -0,5; dextrose -0,5; tinh bột hòa tan -0,5; K2HPO4 -0,3; MgSO4.7H2O -0,005; sodium pyruvate -0,3; thạch -15,0 Yang et al, 2005;Lee et al, 2006;Kim et al, 2011a;Siddiqi et al, 2015;Zhao et al, 2016. R2A pha loãng 5 lần Liu et al, 2006;Yoon & Im, 2007;Jin et al, 2014;Nguyen et al, 2015a;Zhang et al, 2016. R2A pha loãng 10 lần Ten et al, 2006a;Kim et al, 2008c;Srinivasan et al, 2010a;Lee et al, 2011;Kim et al, 2013b.…”