title: Identification of a carboxylesterase-producing Rhodococcus soil isolate.
abstract: Subtropical soil microbial isolates were screened for carbohydrate, tributyrin, or olive oil hydrolysis using agar plates supplemented with the corresponding substrates. A heterotrophic, aerobic, Gram-positive strain displaying activity on tributyrin was selected and further characterized. Analysis of the morphological and physiological traits of the strain placed it as a member of the genus Rhodococcus. Further 16S rDNA sequencing revealed a 99% identity to Rhodococcus erythropolis. The strain displayed lipolytic activity on fatty-acid-derivative substrates of short chain length, with cell extract fractions having highest activity, as confirmed by the presence, after zymogram analysis, of a ca. 60-kDa intracellular protein band with activity on 4-methylumbelliferone-butyrate substrate. The presence of such a lipolytic enzyme, similar to those found in other Gram-positive bacteria, indicates that the strain could be of interest for certain biotechnological applications, like the synthesis of pharmaceuticals or biocide detoxification.
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Spain.
authors.forename: Serena
authors.initials: S
authors.lastname: Falcocchio
authors.forename: Cristian
authors.initials: C
authors.lastname: Ruiz
authors.forename: F I Javier
authors.initials: FI
authors.lastname: Pastor
authors.forename: Luciano
authors.initials: L
authors.lastname: Saso
authors.forename: Pilar
authors.initials: P
authors.lastname: Diaz
mesh_terms: D015373:Bacterial Typing Techniques; D002087:Butyrates / Q000378:metabolism; D043182:Carboxylesterase / Q000096:biosynthesis* / Q000378:metabolism; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal; D006923:Hymecromone / Q000031:analogs & derivatives / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012240:Rhodococcus / Q000145:classification* / Q000201:enzymology* / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
chemical_list: D002087:Butyrates; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D006923:Hymecromone; D043182:Carboxylesterase