ENTEROKOKI OPORNE NA WANKOMYCYNĘ
II. MECHANIZMY OPORNOŚCI, EPIDEMIOLOGIA
Maciej Przybylski
Katedra i Zakład Mikrobiologii Lekarskiej, Akademia Medyczna w
Warszawie
ul.Chałubińskiego 5, 02-004 Warszawa, e-mail: maciej@conexion.pl
Wpłynęło w maju 2007 r.
1. Wstęp.
2. Typy oporności enterokoków na glikopeptydy.
2.1. Typ VanA.
2.2. Typ VanB (VanBl, VanB2 i VanB3). 2.3. Typ VanC
(VanCl, VanC2 i VanC3). 2.4. Typ VanD.
2.5. Typ VanE.
2.6. Typ VanG. 3. Enterokoki
zależne od wankomycyny. 4. Pochodzenie genow
oporności na
antybiotyki
glikopeptydowe u Enterococcus spp.
5. Mechanizm transferu genów. 6. Rozprzestrzenianie
szczepów VRE w oddziałach szpitalnych
Vancomycin-resistant enterococci. II.
Mechanisms of resistance, epidemiology
Abstract:
Antibiotic pressure resulting from the intense use of antibiotics
during the last 60 years has led to the emerging problem of antibiotic
resistance in bacterial strains. Enterococci (especially Enterococcus
faecium) posses a number of intrinsic and acquired
mechanisms
of
resistance. In clinical practice, resistance of Gram-positive cocci
(mostly enterococci) to glycopeptide antibiotics is an important
problem. During the past 15 years our knowledge about genetic
background and molecular mechanisms responsible
for glycopeptide
resistance has been increasing. At present, there are six known types
of enterococcal resistance to glycopeptides (VanA, VanB, VanC, VanD,
VanE and VanG). VanA and VanB types are of major importance because of
the highly efficient mechanism of horizontal gene transfer. The main
reservoir of vanA and vanB
genes are E. faecium
and E. faecalis. VanC,
VanD, VanE and VanG types are rarely found in bacteria isolated from
human clinical specimens but, when present, are also a matter of
concern. The common source of enterococcal van genes is also an
important and interesting problem. Despite extensive search, this
question still needs to be answered.
1. Introduction.
2. Types of glycopeptide resistance in enterococci.
2.1. VanA. 2.2. VanB (VanBl, VanB2 and VanB3).
2.3. VanC (VanCl, VanC2 and
VanC3). 2.4. VanD. 2.5. VanE. 2.6. VanG.
3. Vancomycin-dependent
enterococci. 4. Source of glycopeptide resistance genes
existing in
Enterococcus spp.
5. Mechanism of gene transfer. 6. Spreading of VRE
strains in hospital wards
Słowa kluczowe: geny van, typy
oporności Van,
ruchome elementy
genetyczne, enterokoki oporne na wankomycyny, VRE
Key words: van genes,
Van resistance types, mobile genetic elements,
vancomycin-resistant
enterococci, VRE
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