A Prcliminary Report on a New Enzyme, “Penicillin-amidase”

“…It was not investigated further because ( 1 ) only about 35% of the enzyme in this coupling mixture became attached; (2) the net charge on the cellulose support would result in electrostatic repulsion of the substrate, and (3) there would tend to be a shift in the apparent pH activity profile to the alkaline region, where benzylpenicillin becomes unstable.…”

Section: Discussionmentioning

confidence: 99%

The conversion of benzyl penicillin to 6‐aminopenieillanie acid using an insoluble derivative of penieillin amidase

Self

Kay

Lilly

et al. 1969

Biotech & Bioengineering

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SummaryPenicillin amidase was extracted from Escherichia coli ATCC 9637, grown on phenylacetic acid and glutamate, and purified by fractionation with streptomycin sulphate, ammonium sulphate and polyethylene glycol, followed by chromatography on DEAE-cellulose. The purification factor was 100-200X and the overall yield was about 357,. The enzyme was chemically attached to derivatives of cellulose and the kinetics of these insolubilized penicillin amidase preparations was investigated.

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“…One form of this enzyme, now known to be a p-lactamase (Pollock, 1961), is undoubtedly responsible for the resistance of Staphylococcus aureus to penicillin G (Barber, 1947) ; but it does not explain the high resistance commonly encountered among coliform organisms and other Gram-negative bacilli (Stewart, 1947;Chain, Florey & Jennings, 1949), nor does it explain the resistance of some staphylococci to methicillin (Stewart, 1961 ;Barber & Waterworth, 1962 ;Stewart & Holt, 1963). The work of Sakaguchi & Murao (1950) suggested that some organisms formed an enzyme capable of attacking benzylpenicillin at another locus ; this was later shown (Batchelor et al 1959) to be an amidase capable of liberating 6-aminopenicillanic acid, with lesser antibacterial activity, from penicillin G or…”

Section: Discussionmentioning

confidence: 99%

Production of Amidase and -Lactamase by Bacteria

Holt

Stewart

1964

Journal of General Microbiology

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SUMMARYFresh clinical isolates of Gram-positive and Gram-negative bacteria were tested for the production of p-lactamase and amidase. Techniques for identifying and studying the latter enzyme are described, in relation to its action upon penicillins and other substrates. Various commensal and pathogenic Gram-negative bacilli produce a ' pen-amidase ' of relatively narrow specificity, though no species invariably produces it. A specific pen-amidase was not formed by the Gram-positive bacteria examined, though nonspecific amidases were present. Escherichia coli and paracolon bacilli produced pen-amidase more often than p-lactamase but the Klebsiella-aerogenes group did the reverse. Among other organisms, enzyme production was very variable but absence of either enzyme did not necessarily connote sensitivity of an organism to any penicillin. Administration of penicillin to a patient promotes colonization of the gut and oropharynx by p-lactamaseforming coliforms, but not of amidase-forming organisms. There is a strong association between resistance to the penicillins and formation of p-lactamase by an organism; with pen-amidase, the association is less strong. Neither enzyme accounts completely for bacterial resistance to the penicillins, even within any one species of organism, but the lower resistance of coliforms to ampicillin may be related to the lesser susceptibility of this derivative to amidase.

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A Prcliminary Report on a New Enzyme, “Penicillin-amidase”

Cited by 50 publications

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Model-based experimental analysis of enzyme kinetics in aqueous–organic biphasic systems

Model-based experimental analysis of enzyme kinetics in aqueous–organic biphasic systems

The conversion of benzyl penicillin to 6‐aminopenieillanie acid using an insoluble derivative of penieillin amidase

Production of Amidase and -Lactamase by Bacteria

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