Genotyping of Mycobacterium leprae for better understanding of leprosy transmission in Fortaleza, Northeastern Brazil.

Leprosy is endemic in large part of Brazil with 28,761 new patients in 2015, the second largest number worldwide and reaches 9/10.000 in highly endemic regions and 2.7/10.

Intrapatient comparison of Mycobacterium leprae by VNTR analysis in nasal secretions and skin biopsy in a Brazilian leprosy endemic region.

Background: This study compares the strains of genotypes of M. leprae from nasal secretions (NS) and skin biopsy (SB) in the same patient, supplementing conventional epidemiology to gain insight into the infection of leprosy in Fortaleza, Brazil.

Methods: The sample consisted of 38 newly diagnosed leprosy patients attending the National Reference Center of Dermatology Dona Libania (CDERM), in Fortaleza, who tested positive for M.

Genotyping of Mycobacterium leprae present on Ziehl-Neelsen-stained microscopic slides and in skin biopsy samples from leprosy patients in different geographic regions of Brazil.

We analysed 16 variable number tandem repeats (VNTR) and three single-nucleotide polymorphisms (SNP) in Mycobacterium leprae present on 115 Ziehl-Neelsen (Z-N)-stained slides and in 51 skin biopsy samples derived from leprosy patients from Ceará (n = 23), Pernambuco (n = 41), Rio de Janeiro (n = 22) and Rondônia (RO) (n = 78). All skin biopsies yielded SNP-based genotypes, while 48 of the samples (94.1%) yielded complete VNTR genotypes.

Serum metabolomics reveals higher levels of polyunsaturated fatty acids in lepromatous leprosy: potential markers for susceptibility and pathogenesis.

Background: Leprosy is a disease of the skin and peripheral nervous system caused by the obligate intracellular bacterium Mycobacterium leprae. The clinical presentations of leprosy are spectral, with the severity of disease determined by the balance between the cellular and humoral immune response of the host. The exact mechanisms that facilitate disease susceptibility, onset and progression to certain clinical phenotypes are presently unclear.

Genetic diversity of mycobacterium leprae isolates from Brazilian leprosy patients.

Introduction: Leprosy is a chronic disease caused by infection with Mycobacterium leprae, an obligate intracellular parasite. A problem in studying the transmission of leprosy is the small amount of variation in bacterial genomic DNA. The discovery of variable number of tandem repeats (VNTRs) allowed the detection of strain variation in areas with a high prevalence of leprosy.

Defining mycobacteria: Shared and specific genome features for different lifestyles.

During the last decade, the combination of rapid whole genome sequencing capabilities, application of genetic and computational tools, and establishment of model systems for the study of a range of species for a spectrum of biological questions has enhanced our cumulative knowledge of mycobacteria in terms of their growth properties and requirements. The adaption of the corynebacterial surrogate system has simplified the study of cell wall biosynthetic machinery common to actinobacteria. Comparative genomics supported by experimentation reveals that superimposed on a common core of 'mycobacterial' gene set, pathogenic mycobacteria are endowed with multiple copies of several protein families that encode novel secretion and transport systems such as mce and esx; immunomodulators named PE/PPE proteins, and polyketide synthases for synthesis of complex lipids.

Genotyping North American animal Mycobacterium bovis isolates using multilocus variable number tandem repeat analysis.

Multilocus variable number tandem repeat analysis (MLVA) has recently emerged as a genotyping method that is both robust and highly discriminatory for the differentiation of Mycobacterium tuberculosis complex (MTBC) strains, including Mycobacterium bovis. However, MLVA assessment of M. bovis isolates recovered from animals in North America has been limited.

[Study of rifampin and dapsone resistance in three patients with recurring leprosy].

Objective: To detect the presence of rifampin- and dapsone-resistant strains of Mycobacterium leprae in three patients with recurring leprosy and clinically-suspected antimicrobial resistance through molecular techniques.

Methods: A retrospective, descriptive study was conducted of three multibacillary patients at the "Agua de Dios" Sanitarium in Cundinamarca, Colombia, that presented leprosy relapses that were documented by medical history, bacilloscopy, and biopsy. Biopsies were taken of the skin lesions and the bacteria were subject to DNA extraction and purification.

Biosynthesis of mycobacterial lipoarabinomannan: role of a branching mannosyltransferase.

Lipoarabinomannan (LAM), one of the few known bacterial glycosylphosphoinositides (GPIs), occurs in various structural forms in Mycobacterium species. It has been implicated in key aspects of the physiology of Mycobacterium tuberculosis and the immunology and pathogenesis of tuberculosis. Yet, little is known of the biosynthesis of LAM.

Genetic basis for the synthesis of the immunomodulatory mannose caps of lipoarabinomannan in Mycobacterium tuberculosis.

Lipoarabinomannan (LAM) is a high molecular weight, heterogenous lipoglycan present in abundant quantities in Mycobacterium tuberculosis and many other actinomycetes. In M. tuberculosis, the non-reducing arabinan termini of the LAM are capped with alpha1-->2 mannose residues; in some other species, the arabinan of LAM is not capped or is capped with inositol phosphate.

Roles of conserved proline and glycosyltransferase motifs of EmbC in biosynthesis of lipoarabinomannan.

D-Arabinans, composed of D-arabinofuranose (D-Araf), dominate the structure of mycobacterial cell walls in two settings, as part of lipoarabinomannan (LAM) and arabinogalactan, each with markedly different structures and functions. Little is known of the complexity of their biosynthesis. beta-D-Arabinofuranosyl-1-monophosphoryldecaprenol is the only known sugar donor.

Inactivation of the mycobacterial rhamnosyltransferase, which is needed for the formation of the arabinogalactan-peptidoglycan linker, leads to irreversible loss of viability.

Temperature-sensitive mutant 2-20/32 of Mycobacterium smegmatis mc(2)155 was isolated and genetically complemented with a Mycobacterium tuberculosis H37Rv DNA fragment that contained a single open reading frame. This open reading frame is designated Rv3265c in the M. tuberculosis H37Rv genome.

Comparative analysis of B- and T-cell epitopes of Mycobacterium leprae and Mycobacterium tuberculosis culture filtrate protein 10.

Culture filtrate protein 10 (CFP-10) from Mycobacterium tuberculosis is a well-characterized immunodominant 10-kDa protein antigen known to elicit a very potent early gamma interferon response in T cells from M. tuberculosis-infected mice and humans. The sequence of the Mycobacterium leprae homologue of CFP-10 shows only 40% identity (60% homology) at the protein level with M.

Multiple polymorphic loci for molecular typing of strains of Mycobacterium leprae.

The need for molecular tools for the differentiation of isolates of Mycobacterium leprae, the organism that causes leprosy, is urgent in view of the continuing high levels of new case detection, despite years of aggressive chemotherapy and the consequent reduction in the prevalence of leprosy. The slow onset of leprosy and the reliance on physical examination for detection of disease have restricted the epidemiological tracking necessary to understand and control transmission. Two genetic loci in several isolates of M.

Characterization of the epitope of anti-lipoarabinomannan antibodies as the terminal hexaarabinofuranosyl motif of mycobacterial arabinans.

mAb CS-35 is representative of a large group of antibodies with similar binding specificities that were generated against the Mycobacterium leprae lipopolysaccharide, lipoarabinomannan (LAM), and which cross-reacted extensively with LAMs from Mycobacterium tuberculosis and other mycobacteria. That this antibody also cross-reacts with the arabinogalactan (AG) of the mycobacterial cell wall, suggesting that it recognizes a common arabinofuranosyl (Araf)-containing sequence in AG and LAM, is demonstrated. The antibody reacted more avidly with 'AraLAM' (LAM with naked Araf termini) compared to 'ManLAM' (in which many Araf termini are capped with mannose residues) and mycolylarabinogalactan-peptidoglycan complex (in which the terminal Araf units are substituted with mycolic acids).

Conversion of dTDP-4-keto-6-deoxyglucose to free dTDP-4-keto-rhamnose by the rmIC gene products of Escherichia coli and Mycobacterium tuberculosis.

dTDP-rhamnose is made from glucose-1-phosphate and dTTP by four enzymes encoded by rmIA-D. An Escherichia coli rmIC mutant was constructed and a crude enzyme extract prepared from it did not produce dTDP-4-keto-rhamnose, in contrast to a crude enzyme extract prepared from a wild-type E. coli strain where small amounts of this intermediate were found after incubation with dTDP-glucose in the absence of NADPH.