Binding affinities of β-lactam antibodies for penicillin-binding protein 2' in methicillin-resistant staphylococcus aureus

Yoshihiro Sumita, Masatomo Fukasawa, Susumu Mitsuhashi, Matsuhisa Inoue

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

We devised an accurate procedure with which to measure the affinities of β-lactam antibiotics for penicillin-binding protein (PBP) 2' in methicillin-resistant Staphylococ-cus aureus (MRSA). In the present study, we usedtwo isogenic strains of MRSA, one heterogeneous and the other homogeneous, derived from the methicillin-susceptible strainFDA209P, harbouring the mecA gene. In these MRSA strains, PBP2' was saturated by [14C]benzylpenicillin (PCG) at a concentration of 300 mg/L. In addition, the saturation of PBP2' by [14C]PCG required anincubation period of 30 min. According to these results, the precise affinities of β-lactam antibiotics for PBP2' were determined by the 'accurate competition assay', using a high concentration of [14C]PCG and extending the reaction time. This procedure yielded lower IC50 values of β-lactams than the 'usual competition assay'. However, each β-lactam had almost the same affinity for PBP2' in heterogeneous and homogeneous strains. These results suggest there is a factor(s) other than PBP2' responsible for controlling resistance levels and the heterogeneity or homogeneity of MRSA strains.

Original languageEnglish
Pages (from-to)473-481
Number of pages9
JournalJournal of Antimicrobial Chemotherapy
Volume35
Issue number4
DOIs
Publication statusPublished - Apr 1 1995
Externally publishedYes

Fingerprint

Penicillin-Binding Proteins
Lactams
Methicillin Resistance
Antibody Affinity
Methicillin-Resistant Staphylococcus aureus
Anti-Bacterial Agents
Methicillin
Penicillin G
Inhibitory Concentration 50
Genes

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)
  • Infectious Diseases

Cite this

Binding affinities of β-lactam antibodies for penicillin-binding protein 2' in methicillin-resistant staphylococcus aureus. / Sumita, Yoshihiro; Fukasawa, Masatomo; Mitsuhashi, Susumu; Inoue, Matsuhisa.

In: Journal of Antimicrobial Chemotherapy, Vol. 35, No. 4, 01.04.1995, p. 473-481.

Research output: Contribution to journalArticle

@article{4f651201b03d4df79c12915fb95ee373,
title = "Binding affinities of β-lactam antibodies for penicillin-binding protein 2' in methicillin-resistant staphylococcus aureus",
abstract = "We devised an accurate procedure with which to measure the affinities of β-lactam antibiotics for penicillin-binding protein (PBP) 2' in methicillin-resistant Staphylococ-cus aureus (MRSA). In the present study, we usedtwo isogenic strains of MRSA, one heterogeneous and the other homogeneous, derived from the methicillin-susceptible strainFDA209P, harbouring the mecA gene. In these MRSA strains, PBP2' was saturated by [14C]benzylpenicillin (PCG) at a concentration of 300 mg/L. In addition, the saturation of PBP2' by [14C]PCG required anincubation period of 30 min. According to these results, the precise affinities of β-lactam antibiotics for PBP2' were determined by the 'accurate competition assay', using a high concentration of [14C]PCG and extending the reaction time. This procedure yielded lower IC50 values of β-lactams than the 'usual competition assay'. However, each β-lactam had almost the same affinity for PBP2' in heterogeneous and homogeneous strains. These results suggest there is a factor(s) other than PBP2' responsible for controlling resistance levels and the heterogeneity or homogeneity of MRSA strains.",
author = "Yoshihiro Sumita and Masatomo Fukasawa and Susumu Mitsuhashi and Matsuhisa Inoue",
year = "1995",
month = "4",
day = "1",
doi = "10.1093/jac/35.4.473",
language = "English",
volume = "35",
pages = "473--481",
journal = "Journal of Antimicrobial Chemotherapy",
issn = "0305-7453",
publisher = "Oxford University Press",
number = "4",

}

TY - JOUR

T1 - Binding affinities of β-lactam antibodies for penicillin-binding protein 2' in methicillin-resistant staphylococcus aureus

AU - Sumita, Yoshihiro

AU - Fukasawa, Masatomo

AU - Mitsuhashi, Susumu

AU - Inoue, Matsuhisa

PY - 1995/4/1

Y1 - 1995/4/1

N2 - We devised an accurate procedure with which to measure the affinities of β-lactam antibiotics for penicillin-binding protein (PBP) 2' in methicillin-resistant Staphylococ-cus aureus (MRSA). In the present study, we usedtwo isogenic strains of MRSA, one heterogeneous and the other homogeneous, derived from the methicillin-susceptible strainFDA209P, harbouring the mecA gene. In these MRSA strains, PBP2' was saturated by [14C]benzylpenicillin (PCG) at a concentration of 300 mg/L. In addition, the saturation of PBP2' by [14C]PCG required anincubation period of 30 min. According to these results, the precise affinities of β-lactam antibiotics for PBP2' were determined by the 'accurate competition assay', using a high concentration of [14C]PCG and extending the reaction time. This procedure yielded lower IC50 values of β-lactams than the 'usual competition assay'. However, each β-lactam had almost the same affinity for PBP2' in heterogeneous and homogeneous strains. These results suggest there is a factor(s) other than PBP2' responsible for controlling resistance levels and the heterogeneity or homogeneity of MRSA strains.

AB - We devised an accurate procedure with which to measure the affinities of β-lactam antibiotics for penicillin-binding protein (PBP) 2' in methicillin-resistant Staphylococ-cus aureus (MRSA). In the present study, we usedtwo isogenic strains of MRSA, one heterogeneous and the other homogeneous, derived from the methicillin-susceptible strainFDA209P, harbouring the mecA gene. In these MRSA strains, PBP2' was saturated by [14C]benzylpenicillin (PCG) at a concentration of 300 mg/L. In addition, the saturation of PBP2' by [14C]PCG required anincubation period of 30 min. According to these results, the precise affinities of β-lactam antibiotics for PBP2' were determined by the 'accurate competition assay', using a high concentration of [14C]PCG and extending the reaction time. This procedure yielded lower IC50 values of β-lactams than the 'usual competition assay'. However, each β-lactam had almost the same affinity for PBP2' in heterogeneous and homogeneous strains. These results suggest there is a factor(s) other than PBP2' responsible for controlling resistance levels and the heterogeneity or homogeneity of MRSA strains.

UR - http://www.scopus.com/inward/record.url?scp=0028922221&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028922221&partnerID=8YFLogxK

U2 - 10.1093/jac/35.4.473

DO - 10.1093/jac/35.4.473

M3 - Article

VL - 35

SP - 473

EP - 481

JO - Journal of Antimicrobial Chemotherapy

JF - Journal of Antimicrobial Chemotherapy

SN - 0305-7453

IS - 4

ER -