Fatty and mycolic acids and the pattern of glycolipids were studied in a collection of 34 strains of 'Mycobacterium habana' and in two strains of Mycobacterium simiae. Major glycolipids of these micro-organisms were assigned to the glycopeptidolipid (GPL) structural type, but both mycobacteria differed in the patterns obtained by TLC. The strains of 'M. habana' were separated into four groups (A-D), taking into account the presence or absence of several polar GPLs: group A contained GPL-I, GPL-ll and GPGIII; group B contained GPGI, GPGII', GPGll and GPGIII; group C contained GPGII', GPL-II and GPGIII; group D did not contain any of these compounds. Fatty acids of both bacteria were similar, and ranged from 14 to 26 carbon atoms, hexadecanoic, octadecenoic and tuberculostearic acids being predominant. Mycolic acids were also similar by TLC and HPLC, and consisted of a=, a'-and ketomycolates.Partial structural analysis by M S carried out in strains 'M. habana' TMC 5135 and M. simiae ATCC 25275l revealed that a-and ketomycolates ranged, in general, from 79 to 87 carbon atoms, and a'-mycolates from 58 to 67 carbon atoms. The a-and ketomycolates belonged to several structural series, and minor variations were found between the two strains examined. The data obtained justified the synonymy between 'M. habana' and M. simiae but indicated, in turn, that the former can be distinguished on the basis of GPL analysis. Most strains of 'M. habana' can be defined by the presence of GPGll and GPGIII, a finding that could be useful in the quality control of potential vaccine strains.
A variety of glycolipids were found in a collection of strains of Mycobacterium fortuitum and two patterns were established by thin-layer chromatography. A compound present in all the strains studied was identified as 2,3,4-triacyltrehalose and its overall structure determined by infrared spectroscopy, nuclear magnetic resonance spectroscopy and gas-liquid chromatography-mass spectrometry. Fatty acyl groups present in this molecule were identified as tetradecanoyl, hexadecenoyl, hexadecanoyl, octadecenoyl, octadecanoyl and a variety of 2-methylbranched unsaturated (a-methyl, a,b-unsaturated) acyl groups. The 2-methyl-branched compounds ranged from 17 to 21 carbon atoms, the most abundant being 2-methyloctadecen-2-oyl. Trehalose was the only sugar detected in the glycolipid. This substance immunoreacted with IgG and IgM present in sera from tuberculosis patients, as demonstrated by an enzyme-linked immunosorbent assay.
Three previously healthy children developed gastroenteritis which led within a few days to systemic infections, two cases of bacteremia and one of meningitis. A lactose-fermenting Salmonella virchow strain was isolated from cerebrospinal fluid and blood cultures. In one case, this strain was also isolated from stool cultures. All the children had been fed the same milk formula. There was no other relationship between them. The batch of dried-milk formula was confirmed as the source of the infection by isolation of an identical lactose-fermenting Salmonella virchow strain by the Centro Nacional de Alimentación.
Two strains of Streptococcus pneumoniae isolated from sputum and bronchoalveolar samples with high-level resistance to cefotaxime (MIC = 8 to 16 μg/ml) are described. One of them, belonging to serogroup 19, was also highly resistant to penicillin (MIC = 16 μg/ml), while the other, of serogroup 14, was intermediate in its resistance to penicillin (MIC = 0.25 μg/ml). To our knowledge, these are the first two strains to be isolated in Spain with such high levels of resistance to cefotaxime.
The mycolic acids of several strains of Mycobacterium gordonae were examined by chromatographic and spectroscopic techniques. Both HPLC and TLC revealed two patterns of mycolates among the M. gordonae strains studied. As determined by TLC, one pattern was composed of α-, methoxy-and keto-mycolates ; the other was composed of these mycolates plus an additional component, which was identified as dicarboxy-mycolates. The dicarboxymycolates were only found in those M. gordonae strains that displayed a so-called HPLC-double-cluster pattern. Detailed structural analyses of the dicarboxy-mycolates indicated that these compounds contained predominantly 61-65 carbon atoms (C 63 was the major component) and a trans-1,2-disubstituted cyclopropane ring. Thus, the dicarboxy-mycolate content of strains of M. gordonae determines their HPLC pattern. In spite of the differences in their HPLC patterns, and although they belonged to different PCR-restriction length polymorphism clusters, all of the M. gordonae strains examined in this study were closely related on the basis of the structural features of their α-, keto-and methoxy-mycolates ; the predominant α-mycolates contained two cis-1,2-disubstituted cyclopropane rings, the major keto-mycolates contained a trans-1,2-disubstituted cyclopropane ring and the methoxy-mycolates contained one cis-or one trans-1,2-disubstituted cyclopropane ring. It is noteworthy that the strains containing dicarboxymycolates also displayed significant amounts of α-mycolates that contained one cis-1,2-disubstituted cyclopropane ring and one cis double bond. The results obtained in this study demonstrate heterogeneity among M. gordonae strains.
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