PMID- 9124838
OWN - NLM
STAT- MEDLINE
DCOM- 19970424
LR  - 20200724
IS  - 0066-4804 (Print)
IS  - 1098-6596 (Electronic)
IS  - 0066-4804 (Linking)
VI  - 40
IP  - 12
DP  - 1996 Dec
TI  - Borderline methicillin-susceptible Staphylococcus aureus strains have more in 
      common than reduced susceptibility to penicillinase-resistant penicillins.
PG  - 2769-74
AB  - Ten epidemiologically unrelated Staphylococcus aureus isolates with borderline 
      levels of susceptibility to antistaphylococcal penicillinase-resistant 
      penicillins (PRPs) were investigated together with appropriate S. aureus control 
      strains. By a nitrocefin microplate assay, all borderline PRP-susceptible test 
      strains were found to produce comparable amounts of beta-lactamase. Hydrolytic 
      activity against another chromogenic substrate (PADAC) and against the PRPs was 
      also demonstrated in membrane preparations from induced cells of 9 of the 10 
      borderline test strains. When bacterial membranes were analyzed by sodium dodecyl 
      sulfate-polyacrylamide gel electrophoresis, two methicillin-inducible bands of 
      about 32 and 31 kDa were detected, after Coomassie blue staining, in the membrane 
      protein patterns of the same nine borderline test strains. By gel renaturation 
      and zymographic detection of beta-lactamase activity, both methicillin-inducible 
      membrane proteins were detected with nitrocefin as a substrate, whereas only one 
      band (presumably the smaller protein) was detected with PADAC. With the remaining 
      borderline test strain (a40), only the larger band was detected in the renatured 
      gels with nitrocefin as a substrate. Plasmid DNA analysis revealed that the 
      borderline susceptible test strains, again with the exception of a40, shared a 
      17.2-kb plasmid yielding four HindIII fragments of 7.0, 5.3, 3.5, and 1.4 kb. In 
      Western blot (immunoblot) experiments using rabbit antiserum to 
      penicillin-binding protein (PBP) 2a, test strain a40, which did not share a 
      number of features characteristically associated with the other borderline test 
      strains, was eventually shown to produce PBP 2a. Five other S. aureus strains, 
      belonging to phage group 94/96, were found to display the borderline phenotype, 
      including such distinguishing features as the membrane-associated PRP- and 
      PADAC-hydrolyzing activity, the two methicillin-inducible membrane proteins, and 
      the 17.2-kb plasmid. These results suggest that borderline susceptible S. aureus 
      strains share more common features than reduced susceptibility to PRPs.
FAU - Massidda, O
AU  - Massidda O
AD  - Institute of Microbiology, University of Ancona Medical School, Italy.
FAU - Montanari, M P
AU  - Montanari MP
FAU - Mingoia, M
AU  - Mingoia M
FAU - Varaldo, P E
AU  - Varaldo PE
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Antimicrob Agents Chemother
JT  - Antimicrobial agents and chemotherapy
JID - 0315061
RN  - 0 (Bacterial Proteins)
RN  - 0 (Carrier Proteins)
RN  - 0 (Membrane Proteins)
RN  - 0 (Penicillin-Binding Proteins)
RN  - 0 (Penicillins)
RN  - EC 2.3.2.12 (Peptidyl Transferases)
RN  - EC 2.4.1.- (Hexosyltransferases)
RN  - EC 3.4.17.8 (Muramoylpentapeptide Carboxypeptidase)
RN  - EC 3.5.2.- (Penicillinase)
RN  - Q91FH1328A (Methicillin)
SB  - IM
MH  - *Bacterial Proteins
MH  - Carrier Proteins/analysis
MH  - Drug Resistance, Microbial
MH  - Enzyme Induction
MH  - *Hexosyltransferases
MH  - Membrane Proteins/analysis
MH  - Methicillin/*pharmacology
MH  - Microbial Sensitivity Tests
MH  - Muramoylpentapeptide Carboxypeptidase/analysis
MH  - Penicillin-Binding Proteins
MH  - Penicillinase/*biosynthesis
MH  - Penicillins/*pharmacology
MH  - *Peptidyl Transferases
MH  - Staphylococcus aureus/drug effects/*enzymology/genetics
PMC - PMC163619
EDAT- 1996/12/01 00:00
MHDA- 1996/12/01 00:01
PMCR- 1997/06/01
CRDT- 1996/12/01 00:00
PHST- 1996/12/01 00:00 [pubmed]
PHST- 1996/12/01 00:01 [medline]
PHST- 1996/12/01 00:00 [entrez]
PHST- 1997/06/01 00:00 [pmc-release]
AID - 10.1128/AAC.40.12.2769 [doi]
PST - ppublish
SO  - Antimicrob Agents Chemother. 1996 Dec;40(12):2769-74. doi: 
      10.1128/AAC.40.12.2769.