Sullivan P A, Yin C Y, Molloy C, Templeton M D, Shepherd M G
Can J Microbiol. 1983 Nov;29(11):1514-25. doi: 10.1139/m83-233.
The uptake of nutrients (glucose, glutamine, and N-acetylglucosamine), the intracellular concentrations of metabolites (glucose-6-phosphate, cyclic AMP, amino acids, trehalose, and glycogen) and cell wall composition were studied in Candida albicans. These analyses were carried out with exponential-phase, stationary-phase, and starved yeast cells, and during germ-tube formation. Germ tubes formed during a 3-h incubation of starved yeast cells (0.8 X 10(8) cells/mL) at 37 degrees C during which time the nutrients glucose plus glutamine or N-acetylglucosamine (2.5 mM of each) were completely utilized. Control incubations with these nutrients at 28 degrees C did not form germ tubes. Uptake of N-acetylglucosamine and glutamine was inhibited by cycloheximide which suggests that de novo protein synthesis was required for the induction of these uptake systems. The glucose-6-phosphate content varied from 0.4 nmol/mg dry weight for starved cells to 2-3 nmol/mg dry weight for growing yeast cells and germ tube forming cells. Trehalose content varied from 85 nmol/mg dry weight (growing yeast cells and germ tube forming cells) to 165 nmol/mg weight (stationary-phase cells). The glycogen content decreased during germ-tube formation (from 800 to 600 nmol glucose equivalent/mg dry weight) but increased (to 1000 nmol glucose equivalent/mg dry weight) in the control incubation of yeast cells. Cyclic AMP remained constant throughout germ-tube formation at 4-6 pmol/mg dry weight. The total amino acid pool was similar in exponential, starved, and germ tube forming cells but there were changes in the amounts of individual amino acids. The overall cell wall composition of yeast cells and germ tube forming cells were similar: lipid (2%, w/w); protein (3-6%), and carbohydrate (77-85%). The total carbohydrates were accounted for as the following fractions: alkali-soluble glucan (3-8%), mannan (20-23%), acid-soluble glucan (24-27%), and acid-insoluble glucan (18-26%). The relative amounts of the alkali-soluble and insoluble glucan changed during starvation of yeast cells, reinitiation of yeast-phase growth, and germ-tube formation. Analysis of the insoluble glucan fraction from cells labelled with [14C]glucose during germ-tube formation showed that the chitin content of the cell wall increased from 0.6% to 2.7% (w/w).
对白色念珠菌的营养物质（葡萄糖、谷氨酰胺和N - 乙酰葡糖胺）摄取、代谢物（6 - 磷酸葡萄糖、环磷酸腺苷、氨基酸、海藻糖和糖原）的细胞内浓度以及细胞壁组成进行了研究。这些分析是在指数生长期、稳定期和饥饿的酵母细胞中以及芽管形成过程中进行的。饥饿的酵母细胞（0.8×10⁸个细胞/毫升）在37℃孵育3小时期间形成芽管，在此期间葡萄糖加谷氨酰胺或N - 乙酰葡糖胺（各2.5 mM）这些营养物质被完全利用。在28℃用这些营养物质进行的对照孵育未形成芽管。环己酰亚胺抑制了N - 乙酰葡糖胺和谷氨酰胺的摄取，这表明这些摄取系统的诱导需要从头合成蛋白质。6 - 磷酸葡萄糖含量从饥饿细胞的0.4 nmol/毫克干重变化到生长中的酵母细胞和芽管形成细胞的2 - 3 nmol/毫克干重。海藻糖含量从85 nmol/毫克干重（生长中的酵母细胞和芽管形成细胞）变化到165 nmol/毫克重量（稳定期细胞）。在芽管形成过程中糖原含量下降（从800降至600 nmol葡萄糖当量/毫克干重），但在酵母细胞的对照孵育中增加（至1000 nmol葡萄糖当量/毫克干重）。在整个芽管形成过程中环磷酸腺苷保持恒定，为4 - 6 pmol/毫克干重。指数生长期、饥饿期和芽管形成期细胞中的总氨基酸库相似，但个别氨基酸的量有所变化。酵母细胞和芽管形成细胞的总体细胞壁组成相似：脂质（2%，w/w）；蛋白质（3 - 6%），碳水化合物（77 - 85%）。总碳水化合物分为以下几部分：碱溶性葡聚糖（3 - 8%）、甘露聚糖（20 - 23%）、酸溶性葡聚糖（24 - 27%）和酸不溶性葡聚糖（18 - 26%）。在酵母细胞饥饿、酵母期生长重新开始和芽管形成过程中，碱溶性和不溶性葡聚糖的相对量发生了变化。对芽管形成过程中用[¹⁴C]葡萄糖标记的细胞的不溶性葡聚糖部分进行分析表明，细胞壁的几丁质含量从0.6%增加到2.7%（w/w）。
