Affiliation:
1. Roche Molecular Systems, Alameda, California 94501,1 and
2. Department of Plant Biology, University of California, Berkeley, Berkeley, California 947202
Abstract
ABSTRACT
The phylogeny of 46 geographically diverse
Histoplasma capsulatum
isolates representing the three varieties
capsulatum
,
duboisii
, and
farciminosum
was evaluated using partial DNA sequences of four protein coding genes. Parsimony and distance analysis of the separate genes were generally congruent and analysis of the combined data identified six clades: (i) class 1 North American
H. capsulatum
var.
capsulatum
, (ii) class 2 North American
H. capsulatum
var.
capsulatum
, (iii) Central American
H. capsulatum
var.
capsulatum
, (iv) South American
H. capsulatum
var.
capsulatum
group A, (v) South American
H. capsulatum
var.
capsulatum
group B, and (vi)
H. capsulatum
var.
duboisii
. Although the clades were generally well supported, the relationships among them were not resolved and the nearest outgroups (
Blastomyces
and
Paracoccidioides
) were too distant to unequivocally root the
H. capsulatum
tree.
H. capsulatum
var.
farciminosum
was found within the South American
H. capsulatum
var.
capsulatum
group A clade. With the exception of the South American
H. capsulatum
var.
capsulatum
group A clade, genetic distances within clades were an order of magnitude lower than those between clades, and each clade was supported by a number of shared derived nucleotide substitutions, leading to the conclusion that each clade was genetically isolated from the others. Under a phylogenetic species concept based on possession of multiple shared derived characters, as well as concordance of four gene genealogies,
H. capsulatum
could be considered to harbor six species instead of three varieties.
Publisher
American Society for Microbiology
Reference71 articles.
1. Histoplasmosis—a dual entity: histoplasmosis capsulati and histoplasmosis duboisii;Ajello L.;Ig. Mod.,1983
2. Occurrence of Histoplasma capsulatum Darling, 1906 in Israel, with a review of the current status of histoplasmosis in the Middle East;Ajello L.;Am. J. Trop. Med. Hyg.,1977
3. Principles of genealogical concordance in species concepts and biological taxonomy;Avise J. C.;Oxf. Surv. Evol. Biol.,1990
4. Phylogenetics and the origin of species;Avise J. C.;Proc. Natl. Acad. Sci. USA,1997
5. Choosing among alternative “phylogenetic” species concepts;Baum D. A.;Syst. Bot.,1995
Cited by
161 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献