title: Relationship of some Cryptococcus neoformans hypha-forming strains to standard strains and to other species of yeasts as determined by deoxyribonucleic acid base ratios and homologies.
abstract: The taxonomic relationship between some hypha-forming Cryptococcus neoformans strains and those that morphologically fit the standard description of this species was determined on the basis of DNA base ratios and DNA-DNA duplex formation. The average guanosine plus cytosine content, as estimated from melting temperature profiles, varied between 43.0 and 45.9% for all C. neoformans strains examined. The relative homology was at least 60% for all C. neoformans strains when the labeled DNA was from either a hyphal variant or a standard strain. The nonpathogenic cryptococci, C. laurentii and C. uniguttulatus, showed less than 10% relative homology with either the hyphal or standard C. neoformans strains. Thus, hyphal and standard strains of C. neoformans were sufficiently related to be considered members of the same species.
mesh_terms: D001483:Base Sequence; D003454:Cryptococcus / Q000145:classification*; D003455:Cryptococcus neoformans / Q000032:analysis / Q000145:classification / Q000166:cytology; D004247:DNA / Q000032:analysis* / Q000302:isolation & purification; D009693:Nucleic Acid Hybridization; D012441:Saccharomyces cerevisiae / Q000145:classification* / Q000166:cytology / Q000502:physiology
chemical_list: D004247:DNA