Limits...
High resolution genotyping of clinical Aspergillus flavus isolates from India using microsatellites.

Rudramurthy SM, de Valk HA, Chakrabarti A, Meis JF, Klaassen CH - PLoS ONE (2011)

Bottom Line: All nine markers proved to be polymorphic displaying up to 33 alleles per marker.There is a large genotypic diversity in clinical A. flavus isolates from India.Microsatellites are excellent typing targets for discriminating between A. flavus isolates from various origins.

View Article: PubMed Central - PubMed

Affiliation: Mycology Division, Department of Medical Microbiology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.

ABSTRACT

Background: Worldwide, Aspergillus flavus is the second leading cause of allergic, invasive and colonizing fungal diseases in humans. However, it is the most common species causing fungal rhinosinusitis and eye infections in tropical countries. Despite the growing challenges due to A. flavus, the molecular epidemiology of this fungus has not been well studied. We evaluated the use of microsatellites for high resolution genotyping of A. flavus from India and a possible connection between clinical presentation and genotype of the involved isolate.

Methodology/principal findings: A panel of nine microsatellite markers were selected from the genome of A. flavus NRRL 3357. These markers were used to type 162 clinical isolates of A. flavus. All nine markers proved to be polymorphic displaying up to 33 alleles per marker. Thirteen isolates proved to be a mixture of different genotypes. Among the 149 pure isolates, 124 different genotypes could be recognized. The discriminatory power (D) for the individual markers ranged from 0.657 to 0.954. The D value of the panel of nine markers combined was 0.997. The multiplex multicolor approach was instrumental in rapid typing of a large number of isolates. There was no correlation between genotype and the clinical presentation of the infection.

Conclusions/significance: There is a large genotypic diversity in clinical A. flavus isolates from India. The presence of more than one genotype in clinical samples illustrates the possibility that persons may be colonized by multiple genotypes and that any isolate from a clinical specimen is not necessarily the one actually causing infection. Microsatellites are excellent typing targets for discriminating between A. flavus isolates from various origins.

Show MeSH

Related in: MedlinePlus

Graphical representation of the results.Minimum spanning tree representing the genotypic diversity of 149 clinical A. flavus isolates and a reference isolate using microsatellite typing. The MST is based on a categorical analysis of the data. Each circle represents a unique genotype. The size of the circle corresponds to the number of isolates with the same genotype. The thickness and size of the connecting bars correspond to the number of different markers between linked genotypes. The black genotype is from the reference strain A. flavus NRRL 3357. Genotypes with a shaded background contain 2 or more isolates with identical genotypes or contain genotypes that differ in only 1 microsatellite marker as the possible result of microevolutionary events and are likely to be clonally related.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3022034&req=5

pone-0016086-g001: Graphical representation of the results.Minimum spanning tree representing the genotypic diversity of 149 clinical A. flavus isolates and a reference isolate using microsatellite typing. The MST is based on a categorical analysis of the data. Each circle represents a unique genotype. The size of the circle corresponds to the number of isolates with the same genotype. The thickness and size of the connecting bars correspond to the number of different markers between linked genotypes. The black genotype is from the reference strain A. flavus NRRL 3357. Genotypes with a shaded background contain 2 or more isolates with identical genotypes or contain genotypes that differ in only 1 microsatellite marker as the possible result of microevolutionary events and are likely to be clonally related.

Mentions: A graphical illustration of the observed genotypes showed no correlation between the genotype of the involved isolate and clinical presentation of the infection (Figure 1).


High resolution genotyping of clinical Aspergillus flavus isolates from India using microsatellites.

Rudramurthy SM, de Valk HA, Chakrabarti A, Meis JF, Klaassen CH - PLoS ONE (2011)

Graphical representation of the results.Minimum spanning tree representing the genotypic diversity of 149 clinical A. flavus isolates and a reference isolate using microsatellite typing. The MST is based on a categorical analysis of the data. Each circle represents a unique genotype. The size of the circle corresponds to the number of isolates with the same genotype. The thickness and size of the connecting bars correspond to the number of different markers between linked genotypes. The black genotype is from the reference strain A. flavus NRRL 3357. Genotypes with a shaded background contain 2 or more isolates with identical genotypes or contain genotypes that differ in only 1 microsatellite marker as the possible result of microevolutionary events and are likely to be clonally related.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3022034&req=5

pone-0016086-g001: Graphical representation of the results.Minimum spanning tree representing the genotypic diversity of 149 clinical A. flavus isolates and a reference isolate using microsatellite typing. The MST is based on a categorical analysis of the data. Each circle represents a unique genotype. The size of the circle corresponds to the number of isolates with the same genotype. The thickness and size of the connecting bars correspond to the number of different markers between linked genotypes. The black genotype is from the reference strain A. flavus NRRL 3357. Genotypes with a shaded background contain 2 or more isolates with identical genotypes or contain genotypes that differ in only 1 microsatellite marker as the possible result of microevolutionary events and are likely to be clonally related.
Mentions: A graphical illustration of the observed genotypes showed no correlation between the genotype of the involved isolate and clinical presentation of the infection (Figure 1).

Bottom Line: All nine markers proved to be polymorphic displaying up to 33 alleles per marker.There is a large genotypic diversity in clinical A. flavus isolates from India.Microsatellites are excellent typing targets for discriminating between A. flavus isolates from various origins.

View Article: PubMed Central - PubMed

Affiliation: Mycology Division, Department of Medical Microbiology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.

ABSTRACT

Background: Worldwide, Aspergillus flavus is the second leading cause of allergic, invasive and colonizing fungal diseases in humans. However, it is the most common species causing fungal rhinosinusitis and eye infections in tropical countries. Despite the growing challenges due to A. flavus, the molecular epidemiology of this fungus has not been well studied. We evaluated the use of microsatellites for high resolution genotyping of A. flavus from India and a possible connection between clinical presentation and genotype of the involved isolate.

Methodology/principal findings: A panel of nine microsatellite markers were selected from the genome of A. flavus NRRL 3357. These markers were used to type 162 clinical isolates of A. flavus. All nine markers proved to be polymorphic displaying up to 33 alleles per marker. Thirteen isolates proved to be a mixture of different genotypes. Among the 149 pure isolates, 124 different genotypes could be recognized. The discriminatory power (D) for the individual markers ranged from 0.657 to 0.954. The D value of the panel of nine markers combined was 0.997. The multiplex multicolor approach was instrumental in rapid typing of a large number of isolates. There was no correlation between genotype and the clinical presentation of the infection.

Conclusions/significance: There is a large genotypic diversity in clinical A. flavus isolates from India. The presence of more than one genotype in clinical samples illustrates the possibility that persons may be colonized by multiple genotypes and that any isolate from a clinical specimen is not necessarily the one actually causing infection. Microsatellites are excellent typing targets for discriminating between A. flavus isolates from various origins.

Show MeSH
Related in: MedlinePlus