LIPID CONTENT OF FOUR STRAINS OF BLASTOMYCES DERMATITIDIS OF DIFFERENT MOUSE VIRULENCE

Abstract

content of four strains of Blastomyces dermatitidis of different mouse virulence. J. Bacteriol. 85: 927-931. 1963.-Four strains of Blastomyces dermatitidis showing marked differences in virulence for mice were studied to determine whether there was any relationship between lipid content and virulence. Replicate samples of heat-killed yeast and mycelial cells, after rupturing by grinding, were extrcted with a chloroform-methanol mixture (2:1) in a Soxhlet apparatus for 48 hr. Total extractable lipid was computed by evaporating samples of the extracts to dryness and weighing; the phospholipid fraction was determined by a modified photometric technique. The amount of lipid in the yeast phase of each strain was relatively constant and characteristic as determined by extraction of four samples of each. The extractable lipid increased from 6.8% in the avirulent strain Ga-i to 12.3% in the highly virulent strain SL-1, the lipid content correlating directly with increased mouse virulence. There was no similar correlation of phospholipid content with mouse virulence. The mycelial phases of two strains contained more than double the lipid and phospholipid present in the corresponding yeast phases. Data presented suggest that the lipid fraction of the yeast phase of B. dermatitidis, in addition to being related to the granulomatous reaction, is possibly related to

Maturity as a critical determinant of resistance to fungal infections: studies in murine blastomycosis

“…With a higher CFU challenge, the picture in >25-g mice was identical. 4. Focal nodular areas of infection containing many individual yeast cells (black areas) and inflammatory cells filling the alveolus of a <15-g mouse.…”

Lipids of yeasts.

“…Evidence is available, however, for the protective action of phospholipid against oligomycin action on yeast mitochondrial adenosine 5'-triphosphatase (56,273). Sub-stantiation has not been obtained for a possible correlation between the total cellular phospholipid component in B. dermatitidis (65) and H. capsulatum (213) and virulent properties toward mice.…”

Phospholipid homeostasis maintains cell polarity, development and virulence in metarhizium robertsii

“…Abrogation of the hydrolytic phospholipase genes could disrupt fungal virulence in the human pathogen C. neoformans (Djordjevic, ). However, previous analyses of different isolates from human pathogens failed to find a correlation between the phospholipid content and pathogenic ability (Disalvo and Denton, ; Nielsen, ; Manocha et al ., ). It is well known that the lipid species and their spatial distributions can modulate cell plasma and organelle membrane structures and asymmetry (Janmey and Kinnunen, ; Hishikawa et al ., ).…”

“…In the human pathogen Candida albicans , a glycerol biosynthetic enzyme is required for biofilm formation (Desai et al ., ). However, a comparative analysis failed to find any correlation between phospholipid content and fungal virulence by examining the virulent and avirulent isolates of the mammalian pathogens, Blastomyces dermatitidis (Disalvo and Denton, ), Histoplasma capsulatum (Nielsen, ) and Paracoccidioides brasiliensis (Manocha et al ., ). Nevertheless, relative to the wild types (WT), deletion of phospholipid biosynthesis or hydrolysis genes has been reported to attenuate the virulence of C. albicans (Chen et al ., ) and Cryptococcus neoformans (Djordjevic, ).…”