Ultrastructural changes in bacteria isolated from cases of leprosy

Phenoloxidase activity in organisms isolated from lepromatous and tuberculoid leprosy

Anaerobic corynebacteria (propionibacteria), isolated in pure culture from the plasma of a case of tuberculoid leprosy and from lepromata of cases of lepromatous leprosy, exhibited phenoloxidase activity such as that shown by Prabhakaran to be associated with leprosy bacilli harvested from patients suffering from leprosy. Several corynebacteria, mycobacteria, and nocardias similarly examined did not produce phenoloxidase.

Biological, chemical, immunological and staining properties of bacteria isolated from tissues of leprosy patients

Two kinds of microorganisms are found in tissue of leprosy patients: Mycobacterium leprae (ML) and leprosy derived corynebacteria (LDC). ML from untreated patients has an alcohol-acid-fastness, which is lost upon treatment with antibiotics and immune response (tuberculoid leprosy). Vulnerable ML thus produced can be reversibly de-stained by organic solvent: in tissue sections from tuberculoid and treated patients, more bacteria are, thus, revealed by the Wade-Fite than by the Ziehl-Neelsen procedure. Organisms of genera Corynebacterium, Mycobacterium and Nocardia (CMN group), have DNA with %GC contents of 50-70, 69-72, and 68-70 respectively. GC values of DNA from ML and LDC are close to 56%. DNA from different LDC strains display high homology among them and low homology with reference corynebacteria. CMN cell wall consists of interconnected peptidoglycan and polysaccharide-mycolate complex. Peptidoglycan of LDC (and known CMN) has the polysaccharide backbone linked to a tetrapeptide of L-Ala, D-Glu, m-DAP (meso-diaminopimelate), D-Ala. In ML, L-Ala is replaced by glycine. Mycobacterial wall polysaccharides (that of ML is unknown) are branched arabinogalactans with end arabinoses linked to C70 to C90 mycolates. LDC peripheral polysaccharides are arabinogalactomannans with arabinose and mannose lateral strands. Mycolic acids of LDC are of corynomycolic type (C32, C34 and C36 with 1-4 double bonds) and those of ML are of mycobacterial type. Components of CMN wall and cytoplasm are immunologically active as antigens (polysaccharides, proteins), haptens (lipids) and adjuvants (peptidoglycans). Strong intrageneric and weak intergenera crossreactions are observed among CMN bacteria: LDC preparations, however, crossreact strongly with ML and mycobacteria, and weakly with reference corynebacteria. LDC in leprosy tissues can, thus, be revealed as well by fluorescent anti-LDC antisera as by anti-ML antisera. The main crossreacting component is antigen M1 of LDC, which corresponds to antigens Ag 7 of ML and Ag60 of BCG, the active components of lepromin and tuberculin (known reagents for cutaneous tests). Antigen M1 has a polysaccharide moiety crossreacting with the wall polysaccharide of LDC.(ABSTRACT TRUNCATED AT 400 WORDS)

Description of Corynebacterium tuberculostearicum sp. nov., a leprosy-derived Corynebacterium

Leprosy-derived corynebacteria (LDC) have been extensively studied over the past decade. A composite of their biological properties (cell morphology, staining reactions, cellular inclusions and guanine-plus-cytosine content of their deoxyribonucleic acid; 16 strains studied) and their chemical structures (peptidoglycan type, major cell wall polysaccharide, major glycolipid as well as characteristic mycolic acids) appears to define them as members of the genus Corynebacterium. In relation to other corynebacteria found in humans, including "JK corynebacteria", they seem to be distinct. They are here named Corynebacterium tuberculostearicum sp. nov. because they produce a 10-methyloctadecanoic (tuberculostearic) acid (8 strains studied). This and some of their other attributes are considered in relation to properties of leprosy bacilli and Mycobacterium leprae.

Generation and characterization of monoclonal antibodies to the phenolic glycolipid of Mycobacterium leprae

Nine cloned cell lines producing antibodies to the unique phenolic glycolipid of Mycobacterium leprae have been established as a result of fusions with spleens from mice immunized with the glycolipid complexed with methylated bovine serum albumin. One of the antibodies was relatively nonspecific, binding to a related glycolipid from Mycobacterium kansasii, but the remaining antibodies were specific for the M. leprae lipid. Some of the antibodies required the intact (trisaccharide) carbohydrate portion for recognition of the glycolipid antigen, whereas others recognized partially hydrolyzed forms lacking one or two sugar residues. Monoclonal antibodies directed at the terminal saccharide of the glycolipid showed the greatest specificity for M. leprae in enzyme-linked immunoassays. These antibodies brightly labeled whole mycobacteria in indirect immunofluorescence experiments, demonstrating the surface location of M. leprae-specific determinants of the glycolipid antigen. In addition to their use in providing information about the antigenic properties of the phenolic glycolipid, these antibodies have potential applications for elucidating the roles of glycolipid in the pathogenesis of leprosy.

DNA isolated from Mycobacterium leprae: genome size, base ratio, and homology with other related bacteria as determined by optical DNA-DNA reassociation

DNA derived from Mycobacterium leprae (grown in armadillos) was isolated, purified, and analyzed spectrophotometrically. The genome size and the guanine-plus-cytosine content of M. leprae were 1.3 x 10(9) and 55.8%, respectively. Among selected strains of mycobacterial, nocardial, and corynebacterial species, Corynebacterium sp. 2628 LB, isolated from a human leprosy patient, showed the highest DNA homology with M. leprae. Of the DNAs derived from mycobacteria, those of M. tuberculosis and M. scrofulaceum showed a comparatively high reassociation with the DNMA of M. liprae.

Mycobacterium

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Mesosomes: membranous bacterial organelles

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Chemical characterization of organisms isolated from leprosy patients

CHEMICAL ANALYSES OF THE CELL WALLS OF ORGANISMS ISOLATED IN VARIOUS PARTS OF THE WORLD FROM CASES OF LEPROMATOUS AND TUBERCULOID LEPROSY MAKE POSSIBLE THEIR ASSIGNMENT TO ONE OF THE THREE GENERA: Corynebacterium, Mycobacterium, or Propionibacterium. One, bacterium 22M, remains unassigned. The combined chemical and enzymatic properties attributed to leprosy bacilli freshly harvested from lepromata are found collectively, but not individually, in these three genera.

Cytochemical reactions of human leprosy bacilli and mycobacteria: ultrastructural implications

Leprosy bacilli harvested from freshly biopsied tissue from cases of lepromatous, borderline and histoid leprosy were, in conjunction with Mycobacterium lepraemurium and representative mycobacteria, examined cytochemically with and without their pyridine-extractable acid-fastness. Unlike the mycobacteria, unextracted leprosy bacilli failed to give a positive response to the periodic acid Schiff test or to take up Sudan black B, toluidine blue O, alkaline methylene blue or safranin O. Once their acid-fastness was removed with pyridine, leprosy bacilli were stained by all of the foregoing dyes except Sudan black B, under this condition they remained gram positive. While permanent loss of acid-fastness from leprosy bacilli always resulted in a loss of acid hematein-fixing material (Smith-Dietrich-Baker tests), the reverse was not true. Mild aqueous saponification, bromination, or sequential treatment with lipase and phospholipase D resulted in a loss of acid hematein-positivity but not acid-fastness. After pyridine extraction, bromination, or aqueous saponification, true mycobacteria lost neither their acid hematein-positivity nor their acid-fastness. The acid hematein-positive material and the acid-fastness of both leprosy bacilli and mycobacteria were lost after treatment with alkaline ethanol. These cytochemical findings are discussed in the light of what is known of the ultrastructure of leprosy bacilli and mycobacteria, and of the occurrence of a dl-3, 4-dihydroxyphenylalanine oxidase in leprosy bacilli but not in mycobacteria. An effort is made to explain the rather unique cytochemical properties of leprosy bacilli. Since pyridine-extractable acid-fastness (and acid hematein-positivity) serve to distinguish human leprosy bacilli from M. lepraemurium, one or the other, or both, are suggested as bases for differentiating these two organisms in animal experiments designed to show the in vivo propagation of human leprosy bacilli.

Corynebacterium diphtheriae and its relatives

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Control of morphogenesis in Geodermatophilus: ultrastructural studies

Geodermatophilus grows in two major forms, a nonmotile irregularly shaped aggregate of coccoid cells (C-form) and a motile budding rod (R-form). Morphogenesis can be controlled by an unidentified factor in Tryptose which is required for maintenance of the organism in the C-form and for differentiation of the R-form to the C-form. Morphogenetic events occur synchronously in the described system. Ultrastructural studies show that the major difference between C- and R-forms is in cells envelope structure. R-form cell walls consist of two layers, an inner transparent membranous layer (10 to 12.5 nm thick) and an outer dense diffuse layer (7.5 to 10 nm). In addition to these layers, the C-form has a thick fibrous layer (30 nm) over the dense layer. This layer appears to be a cementing substance which holds the coccoid cells together.