ENZYME ACTIVITY AND CELL DIFFERENTIATION IN NEUROSPORA

摘要: ZALOKAR, MARKO. (Yale U., New Haven, Conn.) Enzyme activity and cell differentiation in Neurospora. Amer. Jour. Bot, 46(7): 555-559. Illus. 1959.-Morphological differences were observed vegetative cells of Neurospora different ages parts the mycelium. The surface layer mycelium grown standing cultures could be separated from deep layer. first contained most growing hyphae rich protoplasm, while second containecl heavily vacuolated laden with fat droplets. Specific activities several enzymes studied conidia, young hyphae, layers mature Succinic dehydrogenase was low conidia about 10 times more active had twice Aldolase increased 3 after germination conidia; it slightly lower than Tryptophan synthetase exhibited only small between f-galactosidase formed appreciable amounts prolonged growth a much higher specific results discussed connection aging. IT HAS BEEN generally that there are progressive changes developing microorganisms, but such have seldom been correlated concurrent morphology. In Neurospora, B8-galactosidase has found to increase age culture (Landman, 1951), tryptophan decreases (Yanofsky, 1952a). It not clear whether these due aging entire or which endowed levels enzyme activities. latter assumption suggested by fact proportion hyphal tips old decreased purpose present study investigate morphologically distinct types mycelia show enzymatic Four enzymes, chosen represent variety functions metabolism, studied: (1) succinic as key citric acid cycle for its localization mitochondria; (2) aldolase an essential glycolysis; (3) 8-galactosidase induced enzyme; (4) constitutive under direct control particular gene Enzymes require either DPN TPN co-factor considered, since they conidial extracts diphosphopyridine nucleotidase (Zalokar Cochrane, 1956). MATERIAL AND METHODS.-Wild-type crassa, E 5297, used all experiments. order obtain large quantities on 500 ml. nitrate medium 1956) 2% agar 'Received publication March 2, 1959. Fernbach flasks. conidiation stimulated if kept days at 30?C. subsequently moved room temperature (20?-25?C.) next 4 days. Conidiation further replacing cotton plugs gauze aeration. yield great 5 g. fresh wt. per flask. Uniform short, separate obtained 200 minimal (Beadle Tatum 1945) 500-ml. Erlenmeyer flasks, vigorously shaken reciprocating shaker inoculated heavy suspension (ca. mg. 100 medium) provide enough material chemical determinations. Older mycelia, free Fries containing Tween 80 (Zalokar, 1954), cultures. Large mycelial mats Roux' flasks media incubation Layers filtration Buchner funnel, described below. would, course, desirable work various similar conditions. This possible, because appropriate obtaining suitable older uniform quality. old, cultures, coalesce into masses sizes unequal structure. size limits amount tissue access surrounding medium. ambiguity avoided where exposure air nutrients is uniform. Standing shaking probably result