Catalytic properties of class A β-lactamases: efficiency and diversity

Enzyme structure and mechanism

1977 • 2,935 citations

Enzyme structure and mechanism

1978 • 2,897 citations

A functional classification scheme for beta-lactamases and its correlation with molecular structure

1995 • 2,497 citations

Inactivation of Antibiotics and the Dissemination of Resistance Genes

1994 • 1,766 citations

The structure of β-lactamases

1980 • 1,705 citations

Multidrug efflux pumps of gram-negative bacteria

1996 • 1,071 citations

Mechanism of action of penicillins: a proposal based on their structural similarity to acyl-D-alanyl-D-alanine.

1965 • 943 citations

Extended-spectrum beta-lactamases

1989 • 808 citations

Nucleotide sequence of the ampicillin resistance gene of Escherichia coli plasmid pBR322.

1978 • 791 citations

More extended-spectrum beta-lactamases

1991 • 740 citations

SERINE β-LACTAMASES AND PENICILLIN-BINDING PROTEINS

1991 • 610 citations

Molecular structure of the acyl-enzyme intermediate in β-lactam hydrolysis at 1.7 Å resolution

1992 • 515 citations

Enzyme structure and mechanism (2nd edn)

1985 • 484 citations

ampC cephalosporinase of Escherichia coli K-12 has a different evolutionary origin from that of beta-lactamases of the penicillinase type.

1981 • 384 citations

Carbapenem-hydrolyzing beta-lactamases

1997 • 360 citations

Crystal structure of Escherichia coli TEM1 β‐lactamase at 1.8 Å resolution

1993 • 349 citations

Bacterial Resistance to β-Lactam Antibiotics: Crystal Structure of β-Lactamase from Staphylococcus aureus PC1 at 2.5 Å Resolution

1987 • 349 citations

The active-site-serine penicillin-recognizing enzymes as members of the Streptomyces R61 <scp>dd</scp>-peptidase family

1988 • 334 citations

Extended-spectrum and inhibitor-resistant TEM-type beta-lactamases: mutations, specificity, and three-dimensional structure

1995 • 313 citations

Refined crystal structure of β-lactamase from Citrobacter freundiiindicates a mechanism for β-lactam hydrolysis

1990 • 299 citations

The Chemistry of β-Lactams

1992 • 277 citations

Evolution of extended-spectrum beta-lactam resistance (SHV-8) in a strain of Escherichia coli during multiple episodes of bacteremia

1997 • 276 citations

Penicillin-Sensitive Enzymes in Peptidoglycan Biosynthesis

1984 • 251 citations

Activities of beta-lactam antibiotics against Escherichia coli strains producing extended-spectrum beta-lactamases

1990 • 226 citations

On the Origin of Bacterial Resistance to Penicillin: Comparison of a β-Lactamase and a Penicillin Target

1986 • 223 citations

.beta.-Lactamase proceeds via an acyl-enzyme intermediate. Interaction of the Escherichia coli RTEM enzyme with cefoxitin

1980 • 222 citations

Refined crystal structure of β-lactamase from Staphylococcus aureus PC1 at 2.0 Å resolution

1991 • 217 citations

Sequences of beta-lactamase genes encoding CTX-M-1 (MEN-1) and CTX-M-2 and relationship of their amino acid sequences with those of other beta-lactamases

1996 • 214 citations

Characterization of IMI-1 beta-lactamase, a class A carbapenem-hydrolyzing enzyme from Enterobacter cloacae

1996 • 212 citations

Characterization of a novel extended-spectrum beta-lactamase from Pseudomonas aeruginosa

1993 • 202 citations

Cloning and sequence of the gene encoding a cefotaxime-hydrolyzing class A beta-lactamase isolated from Escherichia coli

1995 • 201 citations

Evolution of an enzyme activity: crystallographic structure at 2-A resolution of cephalosporinase from the ampC gene of Enterobacter cloacae P99 and comparison with a class A penicillinase.

1993 • 194 citations

An overview of the kinetic parameters of class B β-lactamases

1993 • 192 citations

TEM- and SHV-derived extended-spectrum β-lactamases: relationship between selection, structure and function

1995 • 177 citations

X-ray structure of Streptococcus pneumoniae PBP2x, a primary penicillin target enzyme

1996 • 177 citations

Classification of beta-lactamases: groups 2c, 2d, 2e, 3, and 4

1989 • 176 citations

Cloning and sequence analysis of the gene for a carbapenem-hydrolyzing class A beta-lactamase, Sme-1, from Serratia marcescens S6

1994 • 176 citations

β‐Lactamase of Bacillus licheniformis 749/C at 2 Å resolution

1990 • 175 citations

Amino Acid Sequence Determinants of β-Lactamase Structure and Activity

1996 • 173 citations

Molecular characterisation by PCR-restriction fragment length polymorphism of TEM β-lactamases

1995 • 172 citations

Mechanism of acyl transfer by the class A serine β-lactamase of Streptomyces albus G

1991 • 172 citations

Plasmid-Mediated Resistance to Third-Generation Cephalosporins Caused by Point Mutations in TEM-Type Penicillinase Genes

1988 • 172 citations

The diversity of the catalytic properties of class A β-lactamases

1990 • 169 citations

Comparison of the sequences of class A beta-lactamases and of the secondary structure elements of penicillin-recognizing proteins

1991 • 166 citations

Cell division and peptidoglycan assembly in Eschenchia coli

1991 • 166 citations

Development of "oligotyping" for characterization and molecular epidemiology of TEM beta-lactamases in members of the family Enterobacteriaceae

1990 • 166 citations

Survey and molecular genetics of SHV beta-lactamases in Enterobacteriaceae in Switzerland: two novel enzymes, SHV-11 and SHV-12

1997 • 165 citations

Characterization of a new TEM-type beta-lactamase resistant to clavulanate, sulbactam, and tazobactam in a clinical isolate of Escherichia coli

1993 • 158 citations

Sequence of PSE-2 beta-lactamase

1988 • 156 citations

Analysis of a carbapenem-hydrolyzing class A beta-lactamase from Enterobacter cloacae and of its LysR-type regulatory protein.

1994 • 154 citations

Characterization of beta-lactamase gene blaPER-2, which encodes an extended-spectrum class A beta-lactamase

1996 • 151 citations

Balancing the drug-resistance equation

1994 • 150 citations

Biochemical properties of a carbapenem-hydrolyzing beta-lactamase from Enterobacter cloacae and cloning of the gene into Escherichia coli

1993 • 150 citations

The crystal structure of the β-lactamase of Streptomyces albus G at 0.3 nm resolution

1987 • 149 citations

Incidence and mechanisms of resistance to the combination of amoxicillin and clavulanic acid in Escherichia coli

1995 • 148 citations

Membrane-bound penicillinases in Gram-positive bacteria.

1982 • 142 citations

Genetic and biochemical analysis of a novel Ambler class A beta-lactamase responsible for cefoxitin resistance in Bacteroides species

1993 • 142 citations

Sequence analysis of PER-1 extended-spectrum beta-lactamase from Pseudomonas aeruginosa and comparison with class A beta-lactamases

1994 • 141 citations

β-Lactamase of Bacillus licheniformis 749/C

1991 • 141 citations

Phylogeny of LCR‐1 and OXA‐5 with class A and class D β‐lactamases

1992 • 140 citations

Catalytic hydroxyl/amine dyads within serine proteases

1997 • 139 citations

Site-directed mutants, at position 166, of RTEM-1 beta-lactamase that form a stable acyl-enzyme intermediate with penicillin.

1991 • 137 citations

Close amino acid sequence relationship between the new plasmid-mediated extended-spectrum β-lactamase MEN-1 and chromosomally encoded enzymes of Klebsiella oxytoca

1992 • 135 citations

Site-directed mutagenesis of β-lactamase I. Single and double mutants of Glu-166 and Lys-73

1990 • 135 citations

Tertiary structural similarity between a class A β-lactamase and a penicillin-sensitive D-alanyl carboxypeptidase-transpeptidase

1986 • 134 citations

An efficient method for generating proteins with altered enzymatic properties: application to beta-lactamase.

1989 • 134 citations

TEM β-Lactamase Mutants Hydrolysing Third-generation Cephalosporins

1994 • 128 citations

Molecular evolution of bacterial β-lactam resistance

1996 • 128 citations

SHV-7, a novel cefotaxime-hydrolyzing beta-lactamase, identified in Escherichia coli isolates from hospitalized nursing home patients

1995 • 124 citations

Emergence of clinical isolates of Escherichia coli producing TEM-1 derivatives or an OXA-1 beta-lactamase conferring resistance to beta-lactamase inhibitors

1994 • 123 citations

Nucleotide sequences of the genes coding for the TEM-like β-lactamases IRT-1 and IRT-2 (formerly called TRI-1 and TRI-2)

1994 • 122 citations

Molecular characterization of nine different types of mutants among 107 inhibitor-resistant TEM beta-lactamases from clinical isolates of Escherichia coli

1995 • 120 citations

Clinical isolates of Escherichia coli producing TRI β-lactamases: novel TEM-enzymes conferring resistance to β-lactamase inhibitors

1992 • 119 citations

Intergeneric Transfer of a β-Lactamase Gene between Ps. aeruginosa and E. coli

1970 • 118 citations

The catalytic mechanism of beta-lactamases: NMR titration of an active-site lysine residue of the TEM-1 enzyme.

1996 • 117 citations

Elucidation of the role of arginine-224 in the turnover processes of class A .beta.-lactamases

1992 • 116 citations

A complex mutant of TEM-1 beta-lactamase with mutations encountered in both IRT-4 and extended-spectrum TEM-15, produced by an Escherichia coli clinical isolate

1997 • 114 citations

Metallo-β-lactamases— new therapeutic challenge

1993 • 107 citations

Role of the conserved amino acids of the ‘SDN’ loop (Ser130, Asp131 and Asn132) in a class A β-lactamase studied by site-directed mutagenesis

1990 • 107 citations

Role of Ser-238 and Lys-240 in the hydrolysis of third-generation cephalosporins by SHV-type beta-lactamases probed by site-directed mutagenesis and three-dimensional modeling.

1993 • 106 citations

Nomenclature of TEM beta-lactamases

1997 • 106 citations

Emergence of an inhibitor-resistant beta-lactamase (SHV-10) derived from an SHV-5 variant

1997 • 105 citations

Single amino acid substitution between SHV‐1 β‐lactamase and cefotaxime‐hydrolyzing SHV‐2 enzyme

1988 • 105 citations

Contribution of mutant analysis to the understanding of enzyme catalysis: The case of class A β-lactamases

1995 • 103 citations

Factors determining resistance to β-lactam combined with β-lactamase inhibitors in Escherichia coli

1991 • 100 citations

Transcription and expression analysis, using lacZ and phoA gene fusions, of Mycobacterium fortuitumβ‐lactamase genes cloned from a natural isolate and a high‐level β‐lactamase producer

1994 • 98 citations

Substitution of lysine at position 104 or 240 of TEM-1pTZ18R .beta.-lactamase enhances the effect of serine-164 substitution on hydrolysis or affinity for cephalosporins and the monobactam aztreonam

1991 • 97 citations

Cloning and characterization of the endogenous cephalosporinase gene, cepA, from Bacteroides fragilis reveals a new subgroup of Ambler class A beta-lactamases

1993 • 96 citations

Site-directed mutagenesis at the active site of Escherichia coli TEM-1 beta-lactamase. Suicide inhibitor-resistant mutants reveal the role of arginine 244 and methionine 69 in catalysis.

1992 • 96 citations

Binding of cephalothin and cefotaxime to D-Ala-D-Ala-peptidase reveals a functional basis of a natural mutation in a low-affinity penicillin-binding protein and in extended-spectrum .beta.-lactamases

1995 • 95 citations

Site-directed Mutagenesis of Glutamate 166 in Two β-Lactamases

1997 • 94 citations

Relation between hen egg white lysozyme and bacteriophage T4 lysozyme: Evolutionary implications

1981 • 93 citations

Evolution of antibiotic resistance: several different amino acid substitutions in an active site loop alter the substrate profile of β‐lactamase

1994 • 93 citations

Complete amino acid sequence of p453-plasmid-mediated PIT-2 β-lactamase (SHV-1)

1988 • 92 citations

Systematic mutagenesis of the active site omega loop of TEM-1 beta-lactamase

1996 • 92 citations

Comparative characterization of the cephamycinase blaCMY-1 gene and its relationship with other beta-lactamase genes

1996 • 90 citations

Structure-based design of a potent transition state analogue for TEM-1 β-lactamase

1996 • 87 citations

TEM1 β-lactamase structure solved by molecular replacement and refined structure of the S235A mutant

1995 • 87 citations

Characterization of the plasmid genes blaT-4 and blaT-5 which encode the broad-spectrum β-lactamases TEM-4 and TEM-5 in Enterobacteriaceae

1989 • 81 citations

A Structure-Based Analysis of the Inhibition of Class A .beta.-Lactamases by Sulbactam

1994 • 80 citations

A TEM-derived extended-spectrum beta-lactamase in Pseudomonas aeruginosa

1996 • 77 citations

Structure of a Phosphonate-inhibited β-Lactamase

1993 • 73 citations

β‐lactamase TEM1 of E. coli Crystal structure determination at 2.5 Å resolution

1992 • 72 citations

Transferable resistance to extended-spectrum β-lactams: a major threat or a minor inconvenience?

1991 • 68 citations

Structural basis for the inactivation of the P54 mutant of .beta.-lactamase from Staphylococcus aureus PC1

1991 • 67 citations

First characterization of inhibitor-resistant TEM (IRT) beta-lactamases in Klebsiella pneumoniae strains

1995 • 65 citations

Characterization of TEM-1 beta-lactamase mutants from positions 238 to 241 with increased catalytic efficiency for ceftazidime.

1994 • 65 citations

Evidence for an oxyanion hole in serine β-lactamases and <scp>dd</scp>-peptidases

1988 • 64 citations

Nucleotide sequence of the PSE-4 carbenicillinase gene and correlations with the Staphylococcus aureus PC1 beta-lactamase crystal structure.

1990 • 64 citations

New extended-spectrum TEM-type beta-lactamase from Salmonella enterica subsp. enterica isolated in a nosocomial outbreak

1995 • 63 citations

Catalytic mechanism of active-site serine β-lactamases: role of the conserved hydroxy group of the Lys-Thr(Ser)-Gly triad

1994 • 63 citations

Single amino acid replacements at positions altered in naturally occurring extended-spectrum TEM beta-lactamases

1995 • 59 citations

Characterization of an inhibitor-resistant enzyme IRT-2 derived from TEM-2 β-lactamase produced by Proteus mirabilis strains

1996 • 59 citations

TRC-1: Emergence of a clavulanic acid-resistant TEM β-lactamase in a clinical strain

1992 • 58 citations

Interactions between active-site-serine β-lactamases and compounds bearing a methoxy side chain on the α-face of the β-lactam ring: kinetic and molecular modelling studies

1993 • 54 citations

Multiple substitutions at position 104 of β-lactamase TEM-1: assessing the role of this residue in substrate specificity

1995 • 54 citations

Primary structure of OXA-3 and phylogeny of oxacillin-hydrolyzing class D beta-lactamases

1995 • 53 citations

Molecular evolution of ubiquitous β‐lactamases towards extended‐spectrum enzymes active against newer β‐lactam antibiotics

1990 • 53 citations

Interactions of New Plasmid-Mediated -Lactamases with Third-Generation Cephalosporins

1988 • 53 citations

Small plasmids are involved in amoxicillin-clavulanate resistance in Escherichia coli

1989 • 53 citations

Mass Spectral Kinetic Study of Acylation and Deacylation During the Hydrolysis of Penicillins and Cefotaxime by .beta.-Lactamase TEM-1 and the G238S Mutant

1995 • 52 citations

Electrostatic analysis of TEM1 β-lactamase: effect of substrate binding, steep potential gradients and consequences of site-directed mutations

1995 • 51 citations

Genetically diverse ceftazidime-resistant isolates from a single center: biochemical and genetic characterization of TEM-10 beta-lactamases encoded by different nucleotide sequences

1993 • 51 citations

Biochemical characteristics of extended broad spectrum β-lactamases

1989 • 51 citations

Implication of Ile-69 and Thr-182 residues in kinetic characteristics of IRT-3 (TEM-32) beta-lactamase

1996 • 49 citations

Clinical isolates of Escherichia coli producing multiple TEM mutants resistant to β-lactamase inhibitors

1994 • 48 citations

Sequence of the PSE-1 β-Lactamase Gene

1991 • 47 citations

Nucleotide sequence and phylogeny of SHV-2 beta-lactamase

1990 • 47 citations

Stability of TEM β‐lactamase mutants hydrolyzing third generation cephalosporins

1995 • 46 citations

Substitution of serine for arginine in position 162 of TEM-type β-lactamases extends the substrate profile of mutant enzymes, TEM-7 and TEM-101, to ceftazidime and aztreonam

1989 • 46 citations

The Structures and Catalytic Mechanisms of Active-Site Serine β-Lactamases

1994 • 42 citations

Characterization and amino acid sequence analysis of a new oxyimino cephalosporin-hydrolyzing class A β-lactamase from Serratia fonticola CUV

1997 • 42 citations

Properties of IRT-14 (TEM-45), a newly characterized mutant of TEM-type beta-lactamases

1997 • 42 citations

The Asparagine to Aspartic Acid Substitution at Position 276 of TEM-35 and TEM-36 Is Involved in the β-Lactamase Resistance to Clavulanic Acid

1995 • 41 citations

Chromosomally encoded cephalosporin-hydrolyzing β-lactamase of Proteus vulgaris RO104 belongs to Ambler's class A

1994 • 41 citations

Engineering a novel β-Iactamase by a single point mutation

1990 • 41 citations

Reversal of clavulanate resistance conferred by a Ser-244 mutant of TEM-1 beta-lactamase as a result of a second mutation (Arg to Ser at position 164) that enhances activity against ceftazidime

1994 • 41 citations

Activity of clavulanate combinations against TEM-1 β-lactamase-producing Escherichia coli isolates obtained in 1982 and 1989

1991 • 39 citations

Site‐directed mutagenesis of β‐lactamase TEM‐1

1993 • 39 citations

Cloning and sequence analysis of a class A beta-lactamase from Mycobacterium tuberculosis H37Ra

1997 • 38 citations

OHIO-1 β-lactamase resistant to mechanism-based inactivators

1992 • 37 citations

Characterization of the blaCARB-3 gene encoding the carbenicillinase-3 β-lactamase of Pseudomonas aeruginosa

1991 • 37 citations

New variant of TEM-10 beta-lactamase gene produced by a clinical isolate of proteus mirabilis

1995 • 37 citations

Characterization and amino acid sequence of IRT-4, a novel TEM-type enzyme with a decreased susceptibility to β-lactamase inhibitors

1994 • 36 citations

Characterization of covalently bound enzyme inhibitors as transition-state analogs by protein stability measurements: Phosphonate monoester inhibitors of .beta.-lactamase

1994 • 35 citations

Extrachromosomal resistance in Gram-negative organisms: the evolution of β-lactamase

1994 • 34 citations

A disulfide bridge near the active site of carbapenem-hydrolyzing class A β-lactamases might explain their unusual substrate profile

1997 • 33 citations

Arginine 220 is a critical residue for the catalytic mechanism of the Streptomyces albus G β-lactamase

1991 • 33 citations

β-Lactamase mutations far from the active site influence inhibitor binding

1995 • 33 citations

Critical hydrogen bonding by serine 235 for cephalosporinase activity of TEM-1 beta-lactamase

1993 • 33 citations

Structural Basis of Extended Spectrum TEM β-Lactamases

1996 • 32 citations

Evidence for Structural Elasticity of Class A β-Lactamases in the Course of Catalytic Turnover of the Novel Cephalosporin Cefepime

1996 • 32 citations

Diversity of the mechanisms of resistance to β-lactam antibiotics

1991 • 32 citations

Substitution of Asp for Asn at Position 132 in the Active Site of TEM β -Lactamase

1995 • 32 citations

A Common System Controls the Induction of Very Different Genes. The Class-A beta-Lactamase of Proteus vulgaris and the Enterobacterial Class-C beta-Lactamase

1994 • 32 citations

Does high level production of SHV-type penicillinase confer resistance to ceftazidime in enterobacteriaceae?

1992 • 32 citations

A kinetic study of NMC-A β-lactamase, an Ambler class A carbapenemase also hydrolyzing cephamycins

1996 • 32 citations

Elimination of the Hydrolytic Water Molecule in a Class A β-Lactamase Mutant: Crystal Structure and Kinetics^,

1996 • 31 citations

Bacterial DD-transpeptidases and penicillin.

1995 • 30 citations

Cefotaxime-hydrolysing activity of the β-lactamase ofKlebsiella oxytocaD488 could be related to a threonine residue at position 140

1991 • 30 citations

Replacement of Serine 237 in Class A .beta.-Lactamase of Proteus vulgaris Modifies Its Unique Substrate Specificity

1994 • 30 citations

Structure and Kinetics of the β-Lactamase Mutants S70A and K73H from Staphylococcus aureus PC1^,

1996 • 29 citations

Streptomyces albus G serine β-lactamase. Probing of the catalytic mechanism via molecular modelling of mutant enzymes

1992 • 27 citations

TEM-28 from an Escherichia coli clinical isolate is a member of the His-164 family of TEM-1 extended-spectrum beta-lactamases

1996 • 27 citations

Nucleotide sequence and characterization of a carbenicillin-hydrolyzing penicillinase gene from Proteus mirabilis

1991 • 26 citations

Complementary roles of mutations at positions 69 and 242 in a class A β-lactamase

1995 • 25 citations

Active-site residues of the transpeptidase domain of penicillin-binding protein 2 from Escherichia coli: similarity in catalytic mechanism to class A .beta.-lactamases

1992 • 25 citations

Cloning of chromosomal β-lactamase genes from Yersinia enterocolitica

1991 • 25 citations

Penicillin is an active-site inhibitor for four genera of bacteria

1982 • 24 citations

Citrobacter diversus ULA-27 β-lactamases. Improved purification and general properties

1988 • 23 citations

Probing the active site of β-lactamase R-TEM1 by informational suppression

1990 • 23 citations

Characterization of a novel SHV β-lactamase variant that resembles the SHV-5 enzyme

1996 • 22 citations

Effect of threonine-to-methionine substitution at position 265 on structure and function of TEM-1 beta-lactamase

1994 • 20 citations

Interactions between active‐site serine β‐lactamases and so‐called β‐lactamase‐stable antibiotics

1993 • 20 citations

Sequences of CAZ-3 and CTX-2 extended-spectrum beta-lactamase genes

1994 • 19 citations

Phylogenetic Tree and Sequence Similarity of β-Lactamases

1993 • 17 citations

Site‐directed mutagenesis of the Streptomyces R61 DD‐peptidase

1992 • 16 citations

-Lactamase of Lysobacter Enzymogenes: Induction, Purification and Characterization

1990 • 15 citations

Mutations altering substrate specificity in OHIO-1, and SHV-1 family β-lactamase

1992 • 14 citations

A class-A β-lactamase from Pseudomonas stutzeri that is highly active against monobactams and cefotaxime

1993 • 14 citations

Construction and characterization of an OHIO-1 beta-lactamase bearing Met69Ile and Gly238Ser mutations

1997 • 13 citations

Two variants of transferrable extended-spectrum TEM-β-lactamase successively isolated from a clinical Escherichia coli isolate

1992 • 13 citations

Novel extended-spectrum TEM-type beta-lactamase from an Escherichia coli isolate resistant to ceftazidime and susceptible to cephalothin

1997 • 13 citations

An engineered Staphylococcus aureus PCI ß-lactamase that hydrolyses third-generation cephalosporins

1995 • 12 citations

-Lactamase of Lysobacter enzymogenes: cloning, characterization and expression of the gene and comparison of the enzyme to other lactamases

1993 • 12 citations

An additional ionic bond suggested by molecular modelling of TEM-2 might induce a slight discrepancy between catalytic properties of TEM-1 and TEM-2 β-lactamases

1996 • 10 citations

Beta-lactamases: a major cause of antibiotic resistance.

1988 • 7 citations

Microbiology: Antibiotic resistance and the evolution of bacteria

1983 • 6 citations