The role of lipopolysaccharide anionic binding sites in aminoglycoside uptake in Stenotrophomonas (Xanthomonas) maltophilia.

Aminoglycoside resistance was investigated in six clinical isolates of Stenotrophomonas (Xanthomonas) maltophilia by studying the uptake kinetics and by using a radiochemical method to detect aminoglycoside modifying enzymes. Furthermore, the lipopolysaccharides (LPS) were extracted and characterized by SDS-PAGE and chemical analysis. Dansyl-polymyxin displacement experiments confirmed the availability of anionic binding sites.

Detection by polymerase chain reaction of genes encoding aminoglycoside-modifying enzymes in methicillin-resistant Staphylococcus aureus isolates of epidemic phage types. Belgian Study Group of Hospital Infections (GDEPIH/GOSPIZ).

The polymerase chain reaction (PCR) was used to identify the aacA-aphD, aphA3 and aadC genes, encoding the aminoglycoside-modifying enzymes AAC(6')-APH(2"), APH(3')III and ANT(4'4"), respectively, and the methicillin resistance determinant mecA, in epidemic aminoglycoside and methicillin-resistant isolates of Staphylococcus aureus. In total, 37 isolates collected in the period 1980-1985 and 81 isolates from the period 1991-1992 were obtained from 10 different Belgian hospitals. Epidemic isolates from the earlier period were characterised by phage type C (6/47/54/75) of phage group III, whereas two other epidemic phage types of group III-types A (77) and B (47/54/75/77/84/85)--were commonest in isolates from the second period.

Use of the polymerase chain reaction (PCR) for the detection of aacA genes encoding aminoglycoside-6'-N-acetyltransferases in reference strains and gram-negative clinical isolates from two Belgium hospitals.

Genes encoding aminoglycoside 6'-N-acetyltransferases, were identified using the polymerase chain reaction (PCR). Four sets of primers delineating DNA fragments of 209 bp, 250 bp, 260 bp and 347 bp, specific for the four known aacA genes, and probes within these fragments, were constructed based on the nucleotide sequences of the aacA genes. The specificity of the primers was evaluated using reference strains encoding various aminoglycoside-modifying enzymes.

Identification of the aadB gene coding for the aminoglycoside-2"-O-nucleotidyltransferase, ANT(2"), by means of the polymerase chain reaction.

The polymerase chain reaction (PCR) was used to identify the gene encoding the aminoglycoside-2"-O-nucleotidyltransferase, ANT(2"). Two primers, delineating a DNA fragment of 188 bp, and a specific probe within this fragment were constructed, based on the nucleotide sequence of the aadB gene encoding this enzyme. Reference strains producing different aminoglycoside-modifying enzymes were used to evaluate the specificity and the sensitivity of the test.

Repertoires of antibodies to culture filtrate antigens in different mouse strains infected with Mycobacterium bovis BCG.

Two susceptible (Bcgs) mouse strains, BALB/c and C57BL/6, were compared by Western blot (immunoblot) analysis for their immunoglobulin G response to 14-day-old BCG culture filtrate (CF) following intravenous infection with live Mycobacterium bovis BCG. The two strains demonstrated a completely different antibody repertoire. BALB/c antibodies were directed against a wide range of CF antigens between 20 and about 100 kilodaltons (kDa), with a preferential recognition of the 65-kDa heat shock protein and the 32-kDa fibronectin-binding protein.

H-2-linked control of in vitro gamma interferon production in response to a 32-kilodalton antigen (P32) of Mycobacterium bovis bacillus Calmette-Guérin.

A 32-kilodalton protein antigen (P32) was previously purified to homogeneity from culture filtrate of Mycobacterium bovis BCG (J. De Bruyn, K. Huygen, R.

The production of mycobacterial antigens by homogeneous culture in a fermentor.

Mycobacterium bovis strain BCG, substrain 1173P2, has been grown in homogeneous culture in classical synthetic Sauton medium without supplementary ingredients. The culture conditions are described. The protein release in the culture medium and the tuberculin yield after 2% trichloroacetic acid precipitation were significantly improved.

Purification, characterization and identification of a 32 kDa protein antigen of Mycobacterium bovis BCG.

An immunogenic protein called P32 has been purified from Sauton zinc deficient culture filtrate of Mycobacterium bovis BCG using successively hydrophobic chromatography on Phenyl-Sepharose, ion exchange on DEAE-Sephacel and molecular sieving on Sephadex G-100. The final preparation was found to be homogeneous as based on several analyses. This P32 protein was a constituent of BCG cells grown in normal conditions.