Dimorphism-associated changes in amino acid transport ofCandida albicans

Abstract

Amino acid uptake was followed during pH‐regulated dimorphism of Candida albicans. It was observed that transport activities of various amino acids differed with the morphological phenotype. The uptake rates of l‐alanine, l‐phenylalanine and of l‐lysine were lower and those of l‐methionine were higher in elongated hypha (germ tube), while the rates of glycine, l‐glutamic acid and l‐proline were similar in bud and hyphal phenotypes. Minimum threshold of amino acids transport activity is required at the time of phenotypic commitment in a diverging population of Candida albicans.

Amino acid uptake as a function of differentiation in Candida albicans: studies of a non-germinative variant

“…The transport assay was similar to those described earlier [16,[22][23][24][25][26]. The transport assay was similar to those described earlier [16,[22][23][24][25][26].…”

“…Candida albicans 300 (ATCC 32354) and its non-germinative variant 300 SG were a gift from Dr. D.H. Howard, U.S.A. Cultures were maintained on nutrient agar slants at 4°C [18] and grown in Lee's medium [19] under zinc-deficient conditions [20] as described earlier [16,21].…”

“…Stationary phase G1 singlets (1.5 x 109 cells), maintained as described above, were induced to differentiate at 37°C into yeast and mycelia at pH 4.5 and 6.5, respectively [7,16,21].…”

“…In this communication, a few selected amino acids, L-alanine, L-phenylalanine, L-lysine and Lmethionine, were chosen for transport studies, as our earlier work had demonstrated morphotyperelated changes in uptake during pH-regulated morphological transition in C. albicans ATCC 10261 [16]. However, it was difficult to conclude whether the observed changes in transport activities were a manifestation of the external pH or were specifically related to morphological changes.…”

Asymmetric distribution of phosphatidylethanolamine inC. albicans : possible mediation byCDR1, a multidrug transporter belonging to ATP binding cassette (ABC) superfamily

“…Bud and mycelia were generated by procedure described elsewhere (Kaur et al, 1988). C. albicans 10261 cells were inoculated into 25 ml of amino acid-rich medium (pH 6·8) in plastic Erlenmeyer flasks, and grown at 25 C up to the late log phase of growth (5 10 7 cells/ml).…”