RESUMO
A novel actinomycete, designated strain 06182M-1(T), was isolated from a mangrove soil sample collected from Chiayi County in Taiwan. Phylogenetic analysis based on 16S rRNA gene sequences revealed levels of similarity of 97.0-98.8â% to the type strains of recognized species of the genus Isoptericola. Chemotaxonomic data also supported the placement of strain 06182M-1(T) within the genus Isoptericola. However, the low levels of DNA-DNA relatedness between the novel strain and the type strains of recognized species of the genus Isoptericola, in combination with differential phenotypic data, demonstrate that strain 06182M-1(T) represents a novel species of the genus Isoptericola, for which the name Isoptericola chiayiensis sp. nov. is proposed. The type strain is 06182M-1(T) (â=âBCRC 16888(T) â=âKCTC 19740(T)).
Assuntos
Actinomycetales/classificação , Filogenia , Microbiologia do Solo , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
A novel cell-immobilization technique was developed in this study for increasing substrate partition to the gel matrix by coating a polyurea thin layer on the surface of Ca-alginate beads. The proposed method was simple and could be performed under mild conditions. The bioconversion of progesterone to 11 alpha-hydroxyprogesterone with these polyurea-coating alginate-entrapped Aspergillus ochraceus cells was investigated using different organic solvents in biphasic media. The reaction medium of ethyl acetate could markedly enhance the bioconversion rate with the existence of a hydrophobic layer, most likely resulting from the increasing partition of substrate to gel matrix. Bioconversion with higher substrate concentration was possible using an ethyl acetate-water medium. The conversion rate increased almost linearly with increasing substrate concentration from 10 to 80 g l-1. The rate with 80 g l-1 progesterone increased up to six times greater than the rate with the immobilized cells without coating, and also exhibited a much higher rate than that reported in the literature.