TEM-type beta-lactamase production in Haemophilus ducreyi

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• Haemophilus ducreyi is a Gram-negative bacterium.
• Beta-lactamase enzymes confer resistance to beta-lactam antibiotics.
• Transposons are mobile genetic elements that can carry antibiotic resistance genes.

Purpose of the Study:

• To characterize the beta-lactamase gene present on a plasmid from Haemophilus ducreyi.
• To compare the identified beta-lactamase to known beta-lactamases.

Main Methods:

• Plasmid isolation from Haemophilus ducreyi.
• Molecular characterization of the plasmid (pJB1).
• Sequence analysis of the beta-lactamase gene.

Main Results:

• A 6.0-megadalton plasmid (pJB1) was isolated.
• The plasmid contained a gene coding for a beta-lactamase.
• The beta-lactamase showed similarity to the TEM-1 type, found in ampicillin transposon Tn2.

Conclusions:

• The Haemophilus ducreyi plasmid pJB1 carries a beta-lactamase gene.
• This beta-lactamase is similar to the well-characterized TEM-1 beta-lactamase.
• The presence of such a gene contributes to understanding antibiotic resistance in H. ducreyi.