title: Purification and partial characterization of novel penicillin V acylase from Acinetobacter sp. AP24 isolated from Loktak Lake, an Indo-Burma biodiversity hotspot.
abstract: Members of the bacterial genus Acinetobacter have attracted great attention over the past few decades, on account of their various biotechnological applications and clinical implications. In this study, we are reporting the first experimental penicillin V acylase (PVA) activity from this genus. Penicillin acylases are pharmaceutically important enzymes widely used in the synthesis of semisynthetic beta-lactam antibiotics. The bacterium, identified as Acinetobacter sp. AP24, was isolated from the water of Loktak Lake (Manipur, India), an Indo-Burma biodiversity hotspot. PVA production was increased threefold in an optimized medium with 0.2% sodium glutamate and 1% glucose as nitrogen and carbon sources respectively, after 24 hr of fermentation at 28°C and pH 7.0 with shaking at 180 rpm. The enzyme was purified to homogeneity by cation-exchange chromatography using SP-sepharose resin. The PVA is a homotetramer with subunit molecular mass of 34 kD. The enzyme was highly specific toward penicillin V with optimal hydrolytic activity at 40°C and pH 7.5. The enzyme was stable from pH 5.0 to 9.0 at 25 °C for 2 hr. The enzyme retained 75% activity after 1 hr of incubation at 40°C at pH 7.5.
authors.affiliation: a Biochemical Sciences Division , National Chemical Laboratory , Pune , India.
authors.forename: Pushparani Devi
authors.initials: PD
authors.lastname: Philem
authors.affiliation: b NCIM Resource Centre , National Chemical Laboratory , Pune , India.
authors.forename: Vidya V
authors.initials: VV
authors.lastname: Sonalkar
authors.affiliation: b NCIM Resource Centre , National Chemical Laboratory , Pune , India.
authors.forename: Mahesh S
authors.initials: MS
authors.lastname: Dharne
authors.affiliation: a Biochemical Sciences Division , National Chemical Laboratory , Pune , India.
authors.forename: Asmita A
authors.initials: AA
authors.lastname: Prabhune
mesh_terms: D000150:Acinetobacter / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D044822:Biodiversity; D002850:Chromatography, Gel; D004795:Enzyme Stability; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D007194:India; D002052:Myanmar; D010399:Penicillin Amidase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D010802:Phylogeny; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013379:Substrate Specificity; D013696:Temperature; D014871:Water Microbiology
chemical_list: D010399:Penicillin Amidase
keywords: 6-APA; Acinetobacter; Loktak Lake; penicillin V acylase