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M Harboe

Publications and source records attributed to M Harboe.

220 records · Page 13Linked to original sources
PubMedDate not supplied

Searching for secreted proteins of Mycobacterium leprae.

In mycobacteria secreted proteins represent a distinct group, probably of particular importance for development of immune responses following infection. Quantification of individual proteins in Mycobacterium tuberculosis culture fluid and corresponding disrupted bacilli permits determination of a localization index for identification of secreted proteins. This procedure cannot be applied for Mycobacterium leprae since secreted proteins are lost during isolation of bacilli from tissues. The DNA sequences of secreted proteins of M. tuberculosis were compared with sequences of M. leprae. Genes for homologues of the 85a, 85b, 85c, mpt32 (apa), mpt51, erp, mtc28, mtb12, Rv3354 and Rv0526 genes were identified. All of these and six genes of the mcel operon contain signal sequences for secretion in M. leprae as well. In several instances the local distance between marker genes and occurrence on the same or the complementary DNA strand was similar in these two species. The genomic organization of genes for secreted proteins is thus very similar in M. leprae and M. tuberculosis, the homology being higher for the mature polypeptide chains than for the corresponding signal peptides.

Antigens, Bacterial↗
PubMedDate not supplied

Fatty acid and polar lipid analysis as tools in the identification of Mycobacterium leprae and some related slow-growing mycobacterial species.

Some species of slow-growing Mycobacteria, including Mycobacterium leprae (1 strain), M. lepraemurium (2 strains), M. paratuberculosis (12 strains) and a group of 12 M. avium-like strains (isolates from wild animals) were examined by gas chromatography (GC) for cellular fatty acids and by thin-layer chromatography (TLC) for polar lipids. All the GC patterns, including that of M. leprae, contained high levels of tuberculostearic-, stearic-, octadecenoic- and palmitic acid. Tetradecanoic-, pentadecanoic-, hexadecenoic- and heptadecanoic acid were also generally present but in lower concentrations. In addition to these acids shared by all strains, each bacterial species or group was found to exhibit compounds which were not detected (or detected in considerably lower quantities) in the other taxa examined. Thus each bacterial species or group could be distinguished by their GC profiles. The corresponding TLC patterns were also rather complex. A total of 39 different spots were distinguished. A few of these were shared by all strains, some were characteristic of certain species or groups, whereas others were strain-specific. Both M. leprae and M. lepraemurium shared several features with the other strains but could be distinguished from each other and from the others by their patterns of slow-moving (polar) spots. The 12 M. avium-like strains were divided into two main groups, one with only a few slow-moving spots (rough stains), and one with several slow-moving spots (smooth strains) which included the M. avium reference strains.

Chromatography, Gas↗