[Kinetic characteristics and enantioselective action of penicillinase in the hydrolysis reaction of N-phenylacetyl derivatives of 1-aminoethylphosphonic acid and its esters].
Penicillin acylase from E. coli (EC 3.5.1.11) was found to hydrolyze N-phenylacetylated 1-aminoethylphosphonic acid and its esters. The enzyme preferentially converts the R-form of the substrates: the ratios of the bimolecular rate constants of penicillin acylasecatalyzed hydrolysis of R- and S-forms of 1-(N-phenylacetamino)-ethylphosphonic acid and its dimethyl- and diisopropyl-esters are 58000, 2300, 1800; these derivatives were shown to have the greatest values of the catalytic constants for enzymatic hydrolysis of all known substrates for penicillin acylase: 237, 148 and 134 s-1; the corresponding Km values are 3.7 10(-5), 6.8 10(-4) and 6.2 10(-4) M at pH 7.0. The kinetics of enzymatic hydrolysis of 1-(N-phenylacetamino)-ethylphosphonic acid was investigated up to high degrees of conversion. The inhibition of penicillin acylase by high concentrations of the R-form of the substrate (with substrate inhibition constant of 0.07 M) and competitive inhibition by the reaction product, phenylacetic acid (Ki = 3.5 10(-5) M), was observed.
Mironenko
D A
DA
Kozlova
E V
EV
Shviadas
V K
VK
Solodenko
V A
VA
Kasheva
T N
TN
Kukhar'
V P
VP
D000615:Aminoethylphosphonic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology*; D006868:Hydrolysis; D007700:Kinetics; D063065:Organophosphonates; D010405:Penicillinase / Q000378:metabolism*; D013237:Stereoisomerism
D063065:Organophosphonates; C047639:1-(aminoethyl)phosphonic acid; D000615:Aminoethylphosphonic Acid; D010405:Penicillinase
Kineticheskie zakonomernosti i énantioselektivnost' deĭstviia penitsillinazy v reaktsii gidroliza N-fenilatsetil'nykh proizvodnykh 1-aminoétilfosfonovoĭ kisloty i ee éfirov.