project honey as antimicrobial agent final full.pdf - University of ...

2008; Bacakoglu et al., 2009; Barchitta et al., 2009; Cootz and Marra 2008; Fontana
et al., 2008).
1.3.6 Carbapenem action on Acinetobacter:
Carbapenem is the most effective broad spectrum antibiotic among all of the β-
lactams and imipenem is one of the most important carbapenems (Bergogne-Berezin
et al., 2008). Imipenem is an active agent against many organisms including Gram
positive and Gram negative aerobes and anaerobes. It is a bactericidal agent that kills
or destroys bacteria at 2-4 times the MIC for most species (Greenwood et al., 2003).
The initial step of drug action in destroying bacteria is drug binding to the cell wall
receptors known as penicillin binding proteins (PBPs). The transpeptidation process
is stopped and peptidoglycan synthesis is blocked after β-lactam drug binding to one
or more receptors. The next step involves the removal or suppression of autolytic
enzymes inhibitor in the cell wall. This activates the lytic enzyme which results in
lysis of cells leads to cell death (Brooks et al., 2001).
1.3.7 Mechanisms of Carbapenem Resistance:
There are several complex mechanisms and genetics of resistance acquired by this
species which involve several plasmid-borne β-lactamases and aminoglycoside
modifying enzymes, as well as variation in membrane permeability and alteration in
penicillin-binding proteins. The possession of these multiple mechanisms may be due
to the physiological capability of Acinetobacter and it can obtain DNA by
transformation in vivo (Finch 2003)
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