The laboratory records of patients with bacillus isolates identified as Corynebacterium xerosis were reviewed in an attempt to establish the clinical significance of the isolates, and the isolated ...strains were reidentified. Of the 22 strains available for reidentification, four were identified as Corynebacterium striatum and 18 as Corynebacterium amycolatum. Forty-one patients were considered to have Corynebacterium amycolatum isolates, and in 13 (31.7%) of these patients a genuine clinical infection occurred, comprising catheter-related infection in seven cases, surgical wound infection in five cases, and pilonidal cyst infection in one case. Most patients were treated with antimicrobial agents (vancomycin in seven cases and amoxicillin/clavulanic acid in four cases). All patients were cured. Corynebacterium amycolatum can cause genuine infection, usually hospital-acquired, and the clinical significance of isolates must be determined to ensure proper management of patients.
Thirty-two isolates of Corynebacterium urealyticum, isolated between 1991 and 1995, were studied by biochemical tests, phospholipid content, analysis of fatty and mycolic acids, ribotyping, ...whole-cell protein patterns and antimicrobial susceptibility to six antibiotics. Nineteen isolates were from human and human-related sources (HHRS); the remainder were from animal and animal-related sources (AARS). Most C. urealyticum isolates were similar in their biochemical and whole-cell protein profiles, although most HHRS isolates were alkaline phosphatase-positive (84%) and produced almost identical protein patterns, whereas AARS isolates were quite diverse. The qualitative composition of cellular fatty acids was identical for all isolates examined. Twelve different ribotypes were obtained with HindIII producing four-to-seven bands. Ribotypes 8, 9 and 10 were predominant in isolates from HHRS, whereas in isolates from AARS, ribotypes 5 and 6 predominated. AARS isolates were significantly less antibiotic-resistant, in comparison with HHRS isolates. Ribotyping appeared to be the most useful tool for strain characterisation.
To determine the composition of polar glycopeptidolipids (pGPLs) of Mycobacterium simiae and, particularly, those of 'habana' strains, in a search for specific markers given the immunogenic potential ...of 'habana' TMC 5135 in experimental tuberculosis. pGPLs were determined in free lipid extracts using electrospray ionization-ion trap-mass spectrometry (ESI-IT-MS), working in both negative- and positive-ion mode. In the case of TMC 5135, the presence of the previously characterized GPL-II (containing 2,4-di-O-CH₃ glucuronic acid as distal sugar in the oligosaccharide antigenic moiety) and GPL-III (containing 4-O-CH₃ glucuronic acid as distal sugar) was confirmed using MS/MS and MS/MS/MS approaches. Interestingly, some 'habana' strains presented variants of GPL-II, designated GPL-II'-A and GPL-II'-B. A di-O-CH₃-deoxy-hexose (tentatively, 2,3-di-O-CH₃-fucose) was identified as the penultimate sugar in the oligosaccharide moiety of GPL-II'-A, whereas in GPL-II'-B the penultimate sugar was fucose (tentative identification). On the contrary, the distal sugar of the oligosaccharide chain of pGPLs of Myco. simiae ATCC 25275T was identified as tri-O-CH₃-glucuronic acid (designated GPL-simT-I, with two variants: GPL-simT-I-A and GPL-simT-I-B), O-CH₃-glucuronic acid (designated GPL-simT-II) and di-O-CH₃-glucuronic acid (GPL-II'-A and GPL-II'-B). The penultimate sugar of the oligosaccharide chain of GPL-simT-I-A and GPL-simT-II was identified as di-O-CH₃-deoxy-hexose (tentatively, 2,3-di-O-CH₃ fucose), and that of GPL-simT-I-B as deoxy-hexose (tentatively, fucose). In all strains studied, each M-H⁻ and M+Na⁺ ion was revealed as a mixture of homologous compounds varying in the number of -O-CH₃ groups present in the oligosaccharide moiety and in the length of the fatty acyl linked to the peptide. The present work indicates that, within a similar general pattern of pGPLs, different strains of Myco. simiae present some variations, so that new compounds (GPL-II'-A, GPL-II'-B, GPL-simT-I-A, GPL-simT-I-B and GPL-simT-II) were defined. Noteworthy was the fact that the 'habana' strains clearly differed from the type strain of Myco. simiae. The data obtained can be used in the delineation of the 'habana' group of Myco. simiae, including the quality control of the immunogenic strain 'habana' TMC 5135.
Saturated straight- and branched-chain 3-hydroxy fatty acids (3-OH FAs) of 10–18 carbon chain lengths were determined in saliva from 27 individuals with chronic periodontitis and 18 healthy ...individuals by using gas chromatography–tandem mass spectrometry. Of the 14 different 3-OH FAs detected, 3-OH-C
i17:0 was the most abundant in the periodontitis samples while 3-OH-C
14:0 was the most abundant in the healthy individuals. Considering the relative percentages of 3-OH-C
12:0, 3-OH-C
14:0, 3-OH-C
i17:0, and 3-OH-C
17:0, 95.6% of all cases were correctly classified as healthy individuals or periodontitis patients by means of discriminant analysis. The sensitivity, specificity, positive predictive value and negative predictive value of 3-OH FA analysis in diagnosing peridontitis were, respectively, 0.92, 1.00, 1.00, and 0.90. The results indicate that 3-OH FA analysis of saliva samples is a useful diagnostic method in chronic periodontitis.
A comparative study on phospholipids of Corynebacterium amycolatum, Corynebacterium jeikeium and Corynebacterium urealyticum was carried out using fast-atom bombardment (FAB) and electrospray ...ionization (ESI) mass spectrometry. Data obtained indicate the presence of acylphosphatidylglycerol (APG), diphosphatidylglycerol, phosphatidylglycerol (PG), phosphatidylinositol (PI) and triacylphosphatidylinositol dimannosides (Ac(3)PIM(2)) in these bacteria. In general, octadecenoyl and hexadecanoyl fatty acyl moieties predominated in phospholipids of C. amycolatum, whereas high levels of hexadecenoyl were found in C. jeikeium and C. urealyticum. Mass spectra from purified APG and PG indicated that the sn-1 position of the glycerol was occupied by octadecenoyl in the three species studied. Notably, several major molecular species of PI and Ac(3)PIM(2) from C. urealyticum contained significant amounts of a moiety identified as 10-methyleneoctadecanoyl, located at the sn-1 position of these molecules. On the other hand, multiantibiotic resistant and susceptible strains of C. amycolatum differed in several minor phospholipid fatty acids of 19 carbon atoms, identified as 10-methyloctadecenoic, 10-methyloctadecanoic (tuberculostearic acid) and 10-methyleneoctadecanoic. The results demonstrate an overall similarity among the phospholipids of the different species studied but also significant differences related to the acyl chains of the glycerol moiety of these compounds, notably the high levels of an unusual fatty acyl moiety in inositol-containing phospholipids of C. urealyticum.
A trehalose-containing glycolipid was detected in several strains of Mycobacterium fortuitum and characterized as 2,3-di-O-acyltrehalose (DAT) by combined NMR spectroscopy, IR spectroscopy, GLC and ...GLC-MS. Lipid constituents of the molecule were identified as a mixture of straight-chain (14-18 carbon atoms) and methyl-branched-chain (17-21 carbon atoms) fatty acyl groups. DAT was further fractionated by reverse phase TLC into four fractions that were designated DAT-I-DAT-IV. DAT-I contained 70-75% straight-chain acyl substituents (hexadecanoyl and octadecanoyl predominating) and 25-30% 2-methyl branched substituents (mainly 2-methyl octadecadienoyl). DAT-II was composed of a mixture in which the acyl groups were almost exclusively 2-methyl branched, with 2-methyl octadecadienoyl and 2-methyl octadecen-2-oyl predominating. DAT-III, which was the major isolated fraction, consisted of compounds in which the ratio linear to branched acyl groups varied between 0.8 to 0.9, 2-methyl octadecen-2-oyl, hexadecanoyl and octadecanoyl being the most abundant. Finally, DAT-IV comprised a mixture of DAT molecules containing mostly 2-methyl octadecadienoyl, 2-methyl octadecen-2-oyl, 2-methyl eicosadienoyl and 2-methyl eicosen-2-oyl groups.
‘
Mycobacterium habana’ was proposed as a distinct species within the genus
Mycobacterium; however, it is actually a synonym of
Mycobacterium simiae and included in the serotype I of this species. ...The potential use of ‘
M. habana’ as a vaccine in both leprosy and tuberculosis has led to the analysis of its lipid composition in an attempt to define distinctive markers that could be used in the quality control of true strains of this bacterium. Lipids of taxonomic value (fatty and mycolic acids) are similar in ‘
M. habana’ and
M. simiae; nevertheless, they clearly differ on the basis of glycopeptidolipid (GPL) composition. Thus, contrary to
M. simiae, most strains of ‘
M. habana’ can be defined by the presence of three polar compounds, designated GPL-I, GPL-II and GPL-III, easily determined by thin-layer chromatography, and characterized, respectively, by the content of
l-fucose, 2,4-di-O-Me-
d-glucuronic acid, and 4-O-Me-
d-glucuronic acid, as epitopes.
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 alpha-, methoxy- and keto-mycolates; the other was composed of these mycolates plus an additional component, which was identified as dicarboxy-mycolates. The dicarboxy-mycolates 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 alpha-, keto- and methoxy-mycolates; the predominant alpha-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 dicarboxy-mycolates also displayed significant amounts of alpha-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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