Biomaterial Database

Mycelial- to yeast-phase transitions of the dimorphic fungi Blastomyces dermatitidis and Paracoccidioides brasiliensis. 1987

G Medoff, and A Painter, and G S Kobayashi

The physiological changes that occur during the mycelial- to yeast-phase transitions induced by a temperature shift from 25 to 37 degrees C of cultures of Blastomyces dermatitidis and Paracoccidioides brasiliensis can be divided into three stages. The triggering event is a heat-related insult induced by the temperature shift which results in partial uncoupling of oxidative phosphorylation and declines in cellular ATP levels, respiration rates, and concentrations of electron transport components (stage 1). The cells then enter a stage in which spontaneous respiration ceases (stage 2), and finally, there is a shift into a recovery phase during which transformation to yeast morphology occurs (stage 3). Cysteine is required during stage 2 for the operation of shunt pathways which permit electron transport to bypass blocked portions of the cytochrome system. The mycelial- to yeast-phase transitions of these two fungi are very similar to that of Histoplasma capsulatum. Therefore, these three dimorphic fungal pathogens have evolved parallel mechanisms to adjust to the temperature shifts which induce these mycelial- to yeast-phase transitions.

UI	MeSH Term	Description	Entries
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
D009840	Oligomycins	A closely related group of toxic substances elaborated by various strains of Streptomyces. They are 26-membered macrolides with lactone moieties and double bonds and inhibit various ATPases, causing uncoupling of phosphorylation from mitochondrial respiration. Used as tools in cytochemistry. Some specific oligomycins are RUTAMYCIN, peliomycin, and botrycidin (formerly venturicidin X).	Oligomycin
D010085	Oxidative Phosphorylation	Electron transfer through the cytochrome system liberating free energy which is transformed into high-energy phosphate bonds.	Phosphorylation, Oxidative,Oxidative Phosphorylations,Phosphorylations, Oxidative
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D010228	Paracoccidioides	A mitosporic fungal genus. P. brasiliensis (previously Blastomyces brasiliensis) is the etiologic agent of PARACOCCIDIOIDOMYCOSIS.	Blastomyces brasiliensis,Loboa loboi,Paracoccidioides brasiliensis
D011190	Potassium Cyanide	A highly poisonous compound that is an inhibitor of many metabolic processes, but has been shown to be an especially potent inhibitor of heme enzymes and hemeproteins. It is used in many industrial processes.	Potassium Cyanide (K(14)CN),Potassium Cyanide (K(C(15)N)),Cyanide, Potassium
D001758	Blastomyces	A genus of onygenacetous mitosporic fungi whose perfect state is Ajellomyces (see ONYGENALES). The species Blastomyces dermatitidis (perfect state is Ajellomyces dermatitidis) causes blastomycosis.	Ajellomyces dermatitidis,Blastomycoides dermatitidis,Blastomyces dermatitidis
D002258	Carbonyl Cyanide m-Chlorophenyl Hydrazone	A proton ionophore. It is commonly used as an uncoupling agent and inhibitor of photosynthesis because of its effects on mitochondrial and chloroplast membranes.	CCCP,Carbonyl Cyanide meta-Chlorophenyl Hydrazone,Carbonylcyanide 4-Chlorophenylhydrazone,Propanedinitrile, ((3-chlorophenyl)hydrazono)-,Carbonyl Cyanide m Chlorophenyl Hydrazone,4-Chlorophenylhydrazone, Carbonylcyanide,Carbonyl Cyanide meta Chlorophenyl Hydrazone,Carbonylcyanide 4 Chlorophenylhydrazone
D003545	Cysteine	A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.	Cysteine Hydrochloride,Half-Cystine,L-Cysteine,Zinc Cysteinate,Half Cystine,L Cysteine
D003904	Mitosporic Fungi	A large and heterogenous group of fungi whose common characteristic is the absence of a sexual state. Many of the pathogenic fungi in humans belong to this group.	Deuteromycetes,Deuteromycota,Fungi imperfecti,Fungi, Mitosporic,Hyphomycetes,Deuteromycete,Deuteromycotas,Fungi imperfectus,Fungus, Mitosporic,Hyphomycete,Mitosporic Fungus,imperfectus, Fungi