Escherichia coli DH5О± 13 was used as recipient for cloning and was grown in nutrient broth or on nutrient agar (Oxoid). In all cases, the medium was enriched with вЂ Legionella BCYEвЂ™ growth supplement according to the manufacturerвЂ™s instructions (Oxoid, Basingstoke, UK).

It was plated onto charcoal yeast extract (CYE) agar and grown in 1% w/v yeast extract broth. pneumophila serotype 1 (Philadelphia) (ATCC 33152) 12 was obtained from the ATCC. pneumophila Philadelphia-1 was chosen as the study organism because its genome is currently being sequenced at the Columbia Genome Center, NY, USA. gormanii ATCC 33297 T ОІ-lactamases as a starting point. pneumophila Philadelphia-1 using information about L. 11 The aims of the project described in this report were to analyse the product(s), genetic location(s) and level(s) of expression of the ОІ-lactamase gene(s) from L. gormanii, accounting primarily for resistance to penicillins. It appears that this gene encodes the second ОІ-lactamase of L. 6, 7 In a recent report, the gene bla OXA-29 was cloned from L. gormanii isolates show similar levels of resistance to these agents to L. 8 вЂ“ 10 FEZ-1 does not hydrolyse penicillins, 10 yet L. pneumophila, 7 and is known to produce a metallo-ОІ-lactamase, FEZ-1, which accounts for resistance to cephalosporins and, to a lesser extent, carbapenems. The related bacterium Legionella gormanii shows much broader resistance to ОІ-lactams than L. 3, 5 вЂ“ 7 The sequence of the gene encoding this enzyme has not been reported previously. pneumophila Philadelphia-1 is believed to be due to the production of a single ОІ-lactamase with a pI > 8.0 and a molecular weight of в€ј30 kDa, which hydrolyses penicillins and nitrocefin, but not cephalosporins, and which is inhibited by serine ОІ-lactamase inhibitors. pneumophila Philadelphia-1 being one of the most widely studied, do not display high levels of innate resistance to antibiotics, but it has long been known that they are almost ubiquitously resistant to penicillins in vivo, despite having low MICs of ОІ-lactams in vitro. The fatality rate for Legionella pneumonia can be as high as 50% in immunocompromised patients, but if diagnosed early, antibiotic therapy commonly results in a successful outcome. By far the most common species of Legionella responsible for such infections is Legionella pneumophila. The genus Legionella represents a wide variety of environmental organisms that can, under certain circumstances, cause pneumonia, particularly in debilitated individuals. Received 8 February 2002 returned 26 April 2002 revised accepted 5 June 2002 Introduction pneumophila Philadelphia-1 with ОІ-lactams. Despite the presence of ОІ-lactamase regulator homologues, we could find no evidence of LoxA induction upon challenge of L. The unit consists of loxI, encoding a homologue of the Gram-positive ОІ-lactamase expression regulator, and pbpX, encoding a putative penicillin-binding transpeptidase.

pneumophila Philadelphia-1 chromosome is a two-gene locus similar to that found linked to the ОІ-lactamase genes of Gram-positive bacteria. LoxA is a class 2d penicillinase, and its sequence puts it into the molecular class D ОІ-lactamase family, although phylogenetic analysis shows that LoxA forms a distinct branch in the OXA family along with the LoxA homologue, OXA-29, from Legionella gormanii ATCC 33297 T. pneumophila Philadelphia-1 genome sequencing project. The chromosomal gene that encodes this enzyme, loxA, has been cloned by PCR using information from the L. Legionella pneumophila Philadelphia-1 (ATCC 33152) produces a serine active site ОІ-lactamase.

Pbp3 gene and legionella