scholarly journals The interaction of anthraquinone dyes with the plasmid-mediated OXA-2 β-lactamase

1982 ◽  
Vol 205 (2) ◽  
pp. 413-417 ◽  
Author(s):  
C Monaghan ◽  
S Holland ◽  
J W Dale

Although beta-lactamases do not require any nucleotide co-substrates, the OXA-2 type is inhibited competitively by Cibacron Blue 3GA, and by other anthraquinone dyes, including some simpler compounds with no side chain. The enzyme causes a red shift in the spectrum of Cibacron Blue. The beta-lactamase can be adsorbed in Blue Sepharose and specifically eluted by benzylpenicillin. These results indicate that the binding of anthraquinone dyes is a specific effect similar to that seen with many nucleotide-binding enzymes.

1999 ◽  
Vol 46 (2) ◽  
pp. 419-429 ◽  
Author(s):  
M Danieluk ◽  
R Buś ◽  
S Pikuła ◽  
J Bandorowicz-Pikuła

Annexin VI (AnxVI) from porcine liver, a member of the annexin family of Ca(2+)- and membrane-binding proteins, has been shown to bind ATP in vitro with a K(d) in the low micromolar concentration range. However, this protein does not contain within its primary structure any ATP-binding consensus motifs found in other nucleotide-binding proteins. In addition, binding of ATP to AnxVI resulted in modulation of AnxVI function, which was accompanied by changes in AnxVI affinity to Ca2+ in the presence of ATP. Using limited proteolytic digestion, purification of protein fragments by affinity chromatography on ATP-agarose, and direct sequencing, the ATP-binding site of AnxVI was located in a C-terminal half of the AnxVI molecule. To further study AnxVI-nucleotide interaction we have employed a functional nucleotide analog, Cibacron blue 3GA (CB3GA), a triazine dye which is commonly used to purify multiple ATP-binding proteins and has been described to modulate their activities. We have observed that AnxVI binds to CB3GA immobilized on agarose in a Ca(2+)-dependent manner. Binding is reversed by EGTA and by ATP and, to a lower extent, by other adenine nucleotides. CB3GA binds to AnxVI also in solution, evoking reversible aggregation of protein molecules, which resembles self-association of AnxVI molecules either in solution or on a membrane surface. Our observations support earlier findings that AnxVI is an ATP-binding protein.


1991 ◽  
Vol 278 (3) ◽  
pp. 673-678 ◽  
Author(s):  
J Brannigan ◽  
A Matagne ◽  
F Jacob ◽  
C Damblon ◽  
B Joris ◽  
...  

The lysine-234 residue is highly conserved in beta-lactamases and in nearly all active-site-serine penicillin-recognizing enzymes. Its replacement by a histidine residue in the Streptomyces albus G class A beta-lactamase yielded an enzyme the pH-dependence of which was characterized by the appearance of a novel pK, which could be attributed to the newly introduced residue. At low pH, the kcat, value for benzylpenicillin was as high as 50% of that of the wild-type enzyme, demonstrating that an efficient active site was maintained. Both kcat. and kcat/Km dramatically decreased above pH 6 but the decrease in kcat./Km could not be attributed to larger Km values. Thus a positive charge on the side chain of residue 234 appears to be more essential for transition-state stabilization than for initial recognition of the substrate ground state.


1993 ◽  
Vol 296 (2) ◽  
pp. 389-393 ◽  
Author(s):  
J Rahil ◽  
R F Pratt

A new series of phosphonyl derivatives has been prepared and tested for inhibition of serine (classes A and C) beta-lactamases. The results were compared with those previously acquired with aryl phosphonate monoesters and with alkaline hydrolysis rates. A methyl p-nitrophenyl phosphate monoanion was markedly poorer as an inhibitor of the class C beta-lactamase of Enterobacter cloacae P99 than a comparable p-nitrophenyl phosphonate. Phosphonyl fluorides, thiophenyl esters, N-phenylphosphonamidates and a p-nitrophenyl thionophosphonate were, in general, comparable with p-nitrophenyl phosphonates in inhibitory power. The incorporation of a specific amino side chain led to an increase in the rates of inhibition of around 10(4)-fold. Apparently unresponsive to the addition of the side chain to the enzyme was N-phenyl methylphosphonamidate, where binding of the side chain may interfere with access of the leaving group to a proton which is necessary to active-site phosphonylation and inhibition. Typical class A beta-lactamases were significantly more refractory than the class C enzyme to all of these reagents.


1988 ◽  
Vol 251 (2) ◽  
pp. 453-459 ◽  
Author(s):  
I E Crompton ◽  
B K Cuthbert ◽  
G Lowe ◽  
S G Waley

Many beta-lactamases have active-site serine residues, and are competitively inhibited by boronic acids. Hitherto, the boronic acids used have lacked any structural resemblance to the substrates of beta-lactamases. Phenylacetamidomethaneboronic acid, trifluoroacetamidomethaneboronic acid and 2,6-dimethoxybenzamidomethaneboronic acid have now been synthesized. The first of these contains the side-chain moiety of penicillin G, and the last that of methicillin. The pH-dependence of binding of the first inhibitor to beta-lactamase I from Bacillus cereus revealed pK values of 4.7 and 8.2 for (presumably) active-site groups in the enzyme. The kinetics of inhibition were studied by cryoenzymology and by stopped-flow spectrophotometry. These techniques provided evidence for a two-step mechanism of binding of the first two boronic acids mentioned above to beta-lactamase I, and for benzeneboronic acid to a beta-lactamase from Pseudomonas aeruginosa. The slower step is probably associated with a change in enzyme conformation as well as the formation of an O-B bond between the active-site serine hydroxy group and the boronic acid.


1985 ◽  
Vol 225 (2) ◽  
pp. 435-439 ◽  
Author(s):  
G C Knight ◽  
S G Waley

beta-Lactamases, enzymes that catalyse the hydrolysis of the beta-lactam ring in beta-lactam antibiotics, are divided into three classes, A, B and C, on the basis of the structures so far determined. There are relatively few effective inhibitors of class C beta-lactamases. A beta-lactam sulphone with a hydroxybenzyl side chain, namely (1′R,6R)-6-(1′-hydroxy)benzylpenicillanic acid SS-dioxide (I), has now been studied. The sulphone is a good mechanism-based inhibitor of class C beta-lactamases. At pH8, the inhibition of a Pseudomonas beta-lactamase is irreversible, and proceeds at a rate that is about one-tenth the rate of concurrent hydrolysis. The labelled enzyme has enhanced u.v. absorption and is probably an enamine. At a lower pH, however, inhibition is transitory.


1993 ◽  
Vol 292 (2) ◽  
pp. 555-562 ◽  
Author(s):  
P Ledent ◽  
X Raquet ◽  
B Joris ◽  
J Van Beeumen ◽  
J M Frère

Three class-D beta-lactamases (OXA2, OXA1 and PSE2) were produced and purified to protein homogeneity. 6 beta-Iodopenicillanate inactivated the OXA2 enzyme without detectable turnover. Labelling of the same beta-lactamase with 6 beta-iodo[3H]penicillanate allowed the identification of Ser-70 as the active-site serine residue. In agreement with previous reports, the apparent M(r) of the OXA2 enzyme as determined by molecular-sieve filtration, was significantly higher than that deduced from the gene sequence, but this was not due to an equilibrium between a monomer and a dimer. The heterogeneity of the OXA2 beta-lactamase on ion-exchange chromatography contrasted with the similarity of the catalytic properties of the various forms. A first overview of the enzymic properties of the three ‘oxacillinases’ is presented. With the OXA2 enzyme, ‘burst’ kinetics, implying branched pathways, seemed to prevail with many substrates.


1991 ◽  
Vol 273 (3) ◽  
pp. 503-510 ◽  
Author(s):  
A Matagne ◽  
B Joris ◽  
J Van Beeumen ◽  
J M Frère

Four beta-lactamases excreted by Gram-positive bacteria exhibited microheterogeneity when analysed by chromatofocusing or ion-exchange chromatography. Ragged N-termini were in part responsible for the charge variants, but deamidation of an asparagine residue was also involved, at least for the Bacillus licheniformis enzyme. The activity of a contaminating proteinase could also be demonstrated in the case of Actinomadura R39 beta-lactamase. With that enzyme, proteolysis resulted in partial inactivation, but the inactivated fragments were easily separated from the active forms. With these, as with the other enzymes, the kinetic parameters of the major variants were identical with those of the mixture within the limits of experimental error, so that the catalytic properties of these enzymes can be determined with the ‘heterogeneous’ preparations.


2018 ◽  
Vol 62 (9) ◽  
Author(s):  
Eva Hong ◽  
Ala-Eddine Deghmane ◽  
Muhamed-Kheir Taha

ABSTRACT We report the detection in France of a beta-lactamase-producing invasive meningococcal isolate. Whole-genome sequencing of the isolate revealed a ROB-1-type beta-lactamase gene that is frequently encountered in Haemophilus influenzae, suggesting horizontal transfer between isolates of these bacterial species. Beta-lactamases are exceptional in meningococci, with no reports for more than 2 decades. This report is worrying, as the expansion of such isolates may jeopardize the effective treatment against invasive meningococcal disease.


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