Genotyping Mycobacterium ulcerans and Mycobacterium marinum by Using Mycobacterial Interspersed Repetitive Units

ABSTRACT A novel category of variable tandem repeats (VNTR) called mycobacterial interspersed repetitive units (MIRUs) has been identified for Mycobacterium ulcerans (n = 39), M. marinum (n = 27), and one related organism. Fifteen MIRU loci were identified in the genome of M. marinum and were used to genotype M. ulcerans, M. marinum, and an M. marinum-like organism that is considered a possible missing link between M. marinum and M. ulcerans. Seven MIRU loci were polymorphic, and locus-specific PCRs for four of these loci differentiated seven M. ulcerans genotypes, four M. marinum genotypes, and a unique genotype for the missing link organism. The seven M. ulcerans genotypes were related to six different geographic origins of isolates. All isolates from West and Central Africa, including old and recent isolates, belonged to the same genotype, emphasizing the great spatiotemporal homogeneity among African isolates. Unlike the M. ulcerans genotypes, the four M. marinum genotypes could not be clearly related to the geographic origins of the isolates. According to MIRU-VNTR typing, all M. ulcerans and M. marinum isolates of American origin were closely related, suggesting a common American ancestor for these two pathogenic species on the American continents. MIRU typing has significant potential value for discriminating between reoccurrence and reinfection for M. ulcerans disease.

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Identification of geographical gaps in the pearl millet germplasm conserved at ICRISAT genebank from West and Central Africa

Plant Genetic Resources ◽

10.1017/s147926210999013x ◽

2009 ◽

Vol 8 (1) ◽

pp. 45-51 ◽

Cited By ~ 9

Author(s):

H. D. Upadhyaya ◽

K. N. Reddy ◽

M. Irshad Ahmed ◽

C. L. L. Gowda ◽

B. I. G. Haussmann

Keyword(s):

Pearl Millet ◽

Abiotic Stresses ◽

High Probability ◽

Central Africa ◽

Government Officials ◽

Biotic And Abiotic Stresses ◽

Geographic Origins ◽

Centre Of Diversity ◽

West And Central Africa ◽

Semi Arid

The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) genebank in India holds the world's largest collection of 21,594 pearl millet germplasm accessions including 18,447 landraces from 50 countries. West and Central Africa (WCA) region, which is considered as the centre of diversity for pearl millet, is also an important pearl millet germplasm source for resistance to biotic and abiotic stresses. A total of 7372 landraces were assembled from WCA countries. Out of which, 6434 landraces have the georeference data. The geographic origins of these landraces were analyzed using geographic information system tools to identify gaps in the collection. Geographical distribution of existing collections, type of vegetation, land cover and the high probability (>70%) for the occurrence of pearl millet estimated using the FloraMap software in different countries show that 62 districts in 13 provinces of Nigeria, 50 districts in 16 provinces of Burkina Faso, 9 districts in 6 provinces each of Mali and Mauritania, 8 districts in 8 provinces of Chad and 7 districts in 3 provinces of Ghana as the major geographical gaps in the pearl millet collection at the ICRISAT genebank. In view of this, we suggest that the final areas for exploration in these districts should be decided prior to the launch of the collection missions in consultation with local government officials and extension officers, who have the knowledge of pearl millet cultivation in the districts identified.

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Buruli ulcer: Mycobacterium ulcerans infection

Oxford Textbook of Medicine ◽

10.1093/med/9780198746690.003.0133 ◽

2020 ◽

pp. 1167-1170

Author(s):

Bouke de Jong ◽

Françoise Portaels ◽

Wayne M. Meyers

Keyword(s):

Polymerase Chain Reaction ◽

Subcutaneous Tissue ◽

Buruli Ulcer ◽

Central Africa ◽

Skin Grafting ◽

Surgical Excision ◽

Mycobacterium Ulcerans ◽

West And Central Africa ◽

Cutaneous Nodule ◽

Polymerase Chain

Buruli ulcer is caused by Mycobacterium ulcerans, which secretes a cytotoxic and immunosuppressive toxin, mycolactone. The disease is characterized by necrosis of skin, subcutaneous tissue, and bone, and is re-emerging as a potentially disabling affliction of inhabitants of tropical wetlands. Major foci are in West and Central Africa with an increasing focus in Australia, Mexico, South America, and Southeast Asia. It is not contagious; environmental sources include water, vegetation, and insects, with humans probably becoming infected by traumatic introduction of the bacillus into the skin from the overlying M. ulcerans-contaminated surface in most instances. Clinical presentation may be as a cutaneous nodule, undermined ulcer, plaque, or widely disseminated oedematous lesion. Clinical diagnosis is often accurate by experienced clinicians, and smears for acid-fast bacilli, culture, polymerase chain reaction assays, and histopathology are confirmatory. Treatment was formerly by wide surgical excision and skin grafting, yet antibiotics have now been found effective, including an all-oral regimen.

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Buruli ulcer: Mycobacterium ulcerans infection

Oxford Textbook of Medicine ◽

10.1093/med/9780199204854.003.070628_update_002 ◽

2010 ◽

pp. 848-850

Author(s):

Wayne M. Meyers ◽

Bouke de Jong ◽

Françoise Portaels

Keyword(s):

South America ◽

East Asia ◽

Subcutaneous Tissue ◽

Buruli Ulcer ◽

Central Africa ◽

Mycobacterium Ulcerans ◽

South East Asia ◽

Tropical Wetlands ◽

West And Central Africa ◽

Water Vegetation

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AFLP marker diversity in water yam (Dioscorea alata L.)

Plant Genetic Resources ◽

10.1079/pgr2006121 ◽

2006 ◽

Vol 4 (3) ◽

pp. 181-187 ◽

Cited By ~ 12

Author(s):

C. N. Egesi ◽

R. Asiedu ◽

G. Ude ◽

S. Ogunyemi ◽

J. K. Egunjobi

Keyword(s):

Fragment Length Polymorphism ◽

Aflp Marker ◽

Central Africa ◽

Intraspecific Variability ◽

Dioscorea Alata ◽

Similarity Coefficients ◽

Genetic Groups ◽

Geographic Origins ◽

West And Central Africa ◽

Water Yam

AbstractAmplified fragment length polymorphism (AFLP) markers were employed to assess intraspecific variability in water yam (Dioscorea alata L.). Fifty-three accessions of diverse geographic origins in West and Central Africa (Benin, Côte d'Ivoire, Ghana, Nigeria and Chad) and Puerto Rico were analysed using three AFLP primer combinations. Of the 342 amplification products generated, a mean of 53.4% were polymorphic. Genetic similarity coefficients ranged from 0.29 to 0.95. The accessions could be clustered into three major genetic groups with one outlier. Each group was a mixture of accessions of different geographical origin indicating that geography has not played a major role in the differentiation of the species. A few accessions clustered very tightly suggesting that there may be duplicate accessions in the collection. The wide genetic variation observed constitutes a good basis for genetic improvement of yam.

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Buruli Ulcer (Acha-ere): Pathogenesis and Manifestation

Journal of Advances in Microbiology ◽

10.9734/jamb/2019/v15i330102 ◽

2019 ◽

pp. 1-5

Author(s):

Elendu C. Onwuchekwa ◽

Uzochukwu G. Ekeleme ◽

Oliver Onu-Osi ◽

Okonudo P. Osezele

Keyword(s):

Subcutaneous Tissue ◽

Buruli Ulcer ◽

Central Africa ◽

Mycobacterium Ulcerans ◽

Actin Dynamics ◽

Tropical Regions ◽

West And Central Africa ◽

Chronic Skin ◽

Pass Through ◽

Syndrome Protein

Infection of subcutaneous tissue with Mycobacterium ulcerans can lead to chronic skin ulceration known as Buruli ulcer. It has been reported in over 33 countries around the world, the greatest burden of disease is in the tropical regions of West and Central Africa, Australia, and Japan. It primarily affects children aged 5-15 years. Buruli ulcers generally begin as a painless dermal papule or subcutaneous edematous nodule, which over a period of weeks to months, breaks down to form an extensive necrotic ulcer with undermined edges. The pathogenesis of this neglected tropical disease is dependent on a lipidlike toxin, mycolactone, which diffuses through tissue away from the infecting organisms and elucidate its cytotoxic and immunosuppressive properties. The underlying molecular targets for mycolactone are: First, it can target scaffolding proteins (such as Wiskott Aldrich Syndrome Protein), which control actin dynamics in adherent cells and therefore lead to detachment and cell death. Second, it prevents the co-translational translocation (and therefore production) of many proteins that pass through the endoplasmic reticulum for secretion or placement in cell membranes. Treatment includes a prolonged course of antibiotics and surgical debridement. Early identification and treatment are key, as lesions heal with scarring that can be a significant source of morbidity.

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