title: Isolation and characterization of a new strain of Achromobacter sp. with beta-lactam antibiotic acylase activity.
abstract: A bacterial strain producing a beta-lactam antibiotic acylase, able to hydrolyze ampicillin to 6-aminopenicillanic acid more efficiently than penicillin G, was isolated from soil and characterized. The isolate was identified as Achromobacter sp. using the phenotypic characteristics, composition of cellular fatty acids and 16S rRNA gene sequence. The enzyme synthesis was fully induced by phenylacetic acid (PAA) at a concentration of 2 g l(-1). PAA at concentrations up to 12 g l(-1) had no negative effect on the specific activity of acylase and biomass production, but slowed down the specific growth rate. Benzoic or 4-hydroxyphenylacetic acids can also induce synthesis of the enzyme. The inducers were metabolized in all cases. Acylase activity in cell-free extracts was determined with various substrates; ampicillin, cephalexin and amoxicillin were hydrolyzed 1.5- and 2-times faster than penicillin G. A high stability of acylase activity was observed over a wide range of pH (5.0-8.5) and at temperatures above 55 degrees C.
authors.affiliation: Laboratory of Enzyme Technology, Institute of Microbiology, Academy of Sciences of the Czech Republic, VIdenská 1083, 142 20 Prague 4, Czech Republic. plhacko@biomed.cas.cz
authors.forename: K
authors.initials: K
authors.lastname: Plhácková
authors.forename: S
authors.initials: S
authors.lastname: Becka
authors.forename: F
authors.initials: F
authors.lastname: Skrob
authors.forename: P
authors.initials: P
authors.lastname: Kyslík
mesh_terms: D042402:Achromobacter / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D019817:Benzoic Acid / Q000378:metabolism; D004275:DNA, Ribosomal / Q000737:chemistry; D004790:Enzyme Induction; D004795:Enzyme Stability; D005838:Genotype; D006863:Hydrogen-Ion Concentration; D010399:Penicillin Amidase / Q000096:biosynthesis / Q000378:metabolism*; D010641:Phenotype; D010648:Phenylacetates / Q000378:metabolism / Q000494:pharmacology; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology; D013379:Substrate Specificity; D013696:Temperature; D047090:beta-Lactams / Q000378:metabolism*
chemical_list: D004275:DNA, Ribosomal; D010648:Phenylacetates; D012336:RNA, Ribosomal, 16S; D047090:beta-Lactams; C008070:4-hydroxyphenylacetic acid; D019817:Benzoic Acid; C049057:ampicillin acylase; D010399:Penicillin Amidase; C025136:phenylacetic acid