scholarly journals Penicillin-binding proteins and induction of AmpC beta-lactamase.

1997 ◽  
Vol 41 (9) ◽  
pp. 2013-2015 ◽  
Author(s):  
C C Sanders ◽  
P A Bradford ◽  
A F Ehrhardt ◽  
K Bush ◽  
K D Young ◽  
...  
Keyword(s):  
Binding Proteins ◽  
Beta Lactamase ◽  
Penicillin Binding Proteins ◽  
Very High ◽  
Competition Assays

In competition assays for radiolabeled penicillin, penicillin-binding proteins (PBPs) 4, 7a, and 7b showed very high affinities for strong inducers of AmpC beta-lactamase. Loss of PBP 4 resulted in diminished inducibility. This suggests that if PBPs are involved in induction of AmpC beta-lactamase, there is probably a redundancy in function among the different PBPs.

scholarly journals Distinctive Binding of Avibactam to Penicillin-Binding Proteins of Gram-Negative and Gram-Positive Bacteria

2015 ◽  
Vol 60 (2) ◽  
pp. 752-756 ◽  
Author(s):  
Abdelhamid Asli ◽  
Eric Brouillette ◽  
Kevin M. Krause ◽  
Wright W. Nichols ◽  
François Malouin
Keyword(s):  
Binding Proteins ◽  
New Combination ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Content Type ◽  
Penicillin Binding Proteins ◽  
Gram Positive Bacteria ◽  
Fixed Concentration ◽  
Competition Assays

ABSTRACTAvibactam is a novel non-β-lactam β-lactamase inhibitor that covalently acylates a variety of β-lactamases, causing inhibition. Although avibactam presents limited antibacterial activity, its acylation ability toward bacterial penicillin-binding proteins (PBPs) was investigated.Staphylococcus aureuswas of particular interest due to the reported β-lactamase activity of PBP4. The binding of avibactam to PBPs was measured by adding increasing concentrations to membrane preparations of a variety of Gram-positive and Gram-negative bacteria prior to addition of the fluorescent reagent Bocillin FL. Relative binding (measured here as the 50% inhibitory concentration [IC50]) to PBPs was estimated by quantification of fluorescence after gel electrophoresis. Avibactam was found to selectively bind to some PBPs. InEscherichia coli,Pseudomonas aeruginosa,Haemophilus influenzae, andS. aureus, avibactam primarily bound to PBP2, with IC50s of 0.92, 1.1, 3.0, and 51 μg/ml, respectively, whereas binding to PBP3 was observed inStreptococcus pneumoniae(IC50, 8.1 μg/ml). Interestingly, avibactam was able to significantly enhance labeling ofS. aureusPBP4 by Bocillin FL. In PBP competition assays withS. aureus, where avibactam was used at a fixed concentration in combination with varied amounts of ceftazidime, the apparent IC50of ceftazidime was found to be very similar to that determined for ceftazidime when used alone. In conclusion, avibactam is able to covalently bind to some bacterial PBPs. Identification of those PBP targets may allow the development of new diazabicyclooctane derivatives with improved affinity for PBPs or new combination therapies that act on multiple PBP targets.

scholarly journals Non-Beta-Lactamase-Producing Penicillin-ResistantEnterococcus faeciumin a Clinical Setting

1990 ◽  
Vol 1 (3) ◽  
pp. 73-76 ◽  
Author(s):  
Daniel Eymard ◽  
Andre Dascal ◽  
John Hiscott ◽  
Sonia Gioseffini ◽  
Janet Stevenson ◽  
...  
Keyword(s):  
Clinical Setting ◽  
Plasmid Dna ◽  
Enterococcus Faecium ◽  
Binding Proteins ◽  
Clinical Isolates ◽  
Beta Lactamase ◽  
Penicillin Binding Proteins ◽  
Mechanism Of Resistance

Six clinical isolates ofEnterococcus faeciumhighly resistant to penicillin are reported. These strains did not produce beta-lactamase and no plasmid DNA could be detected. It is postulated that the mechanism of resistance is one or more chromosomally mediated alterations of penicillin-binding proteins.

scholarly journals Draft Genome Sequences of Extended-Spectrum-Beta-Lactamase-Producing Morganella morganii Strains AA1 and AV1, Isolated from a Freshwater Lake and Eicchorniacrassipes Roots

2017 ◽  
Vol 5 (24) ◽  
Author(s):  
Pushpa Lata ◽  
Subramaniam S. Govindarajan ◽  
Feng Qi ◽  
Jian-Liang Li ◽  
Santosh K. Maurya ◽  
...  
Keyword(s):  
Binding Proteins ◽  
Draft Genome ◽  
Beta Lactamase ◽  
Genome Sequences ◽  
Morganella Morganii ◽  
Coding Sequences ◽  
Content Type ◽  
Beta Lactamases ◽  
Penicillin Binding Proteins ◽  
Extended Spectrum Beta Lactamase

ABSTRACT Two strains of Morganella morganii, AA1 and AV1, were isolated from freshwater and Eicchornia crassipes roots, respectively. Here, we report their draft genome sequences, which are ~3.6 Mb and have 51% G+C content. The predicted coding sequences (3,259 for strain AA1 and 3,345 for strain AV1) encode beta-lactamases, transpeptidases, and penicillin-binding proteins.

Sign in / Sign up

Export Citation Format

Share Document