Enzyme activities during the asexual cycle of Neurospora crassa. III. Nicotinamide adenosine diphosphate glycohydrolase

Abstract

STINE, G. J. 1969. Enzyme activities during the asexual cycle of Neurospora crassa. 111. Nicotinamide adenosine diphosphate glycohydrolase. Can. J. Microbial. 15: 1249-1254. The level and specific activity of nicotinamide adenosine diphosphate glycohydrolase (NADase) were followed throughout the asexual cycle in Nelrrospora crassa. A large quantity of NADase associated with the conidia was water soluble. NADase activity rapidly disappeared from the growth medium during conidial germination and from early logarithmic mycelial growth. As the mycelia aged, the enzyme accumulated in the growth medium and in the aging aconidial conidiophores, regardless of their inability to produce conidia. Since the enzyme was synthesized as the culture aged, it appears that the conidiophores age quickly with respect to their production of NADase. Conidia produced from conidiophores of the wild-type culture contained about the same quantity of NADase as the inoculum conidia. The accumulation of NADase in the conidia of wild-type Neurospora is due to the normal differentiation of these conidia in the absence of a liquid environment. The enzyme becomes locked into the conidia being differcntiated from conidiophores that contain large amounts of the NADase activity.

A nicotinamide adenine dinucleotide (phosphate) glycohydrolase [NAD(P)ase, EC 3.2.2.6] fromStreptomyces griseus

“…griseus NAD(P)ase is accumulated in the culture fluid. Similar observations 247 have been reported for several other bacteria and fungi [8,13,18]. NADase activity in a viomycinproducing strain ofS.…”

“…In Neurospora crassa the enzyme is thought to participate in the control of morphological development [18]. However, up to now it is not possible to draw any firm conclusions.…”

Biochemical genetics of Neurospora crassa conidial germination.

“…The enzyme as isolated from zinc-starved mycelia is a glycoprotein and has a ratio of carbohydrate to protein of about 6:1 (52). Conidia contain high levels of this enzyme activity which can be almost completely removed by washing with water (194,241). NADase cannot be detected in log-phase vegetative mycelia (186,215) or in N. crassa ascospores (186).…”

Distribution of Wall-bound Invertase during the Asexual Life-cycle of Neurospora crassa

“…Fungal development is usually accompanied by changes in enzyme activities (Zalokar, 1959;Nagasaki, 1968;Stine, 1969). A few mural exoenzymes in fungi are also present in amounts that vary with the age of the organism (Horikoshi & Ikeda, 1965;Mahadevan & Mahadkar, 1970 Trevithick, 1972) this report records its changing distribution in the wall fraction during the Neurospora asexual lifecycle, as represented by six cytologically distinct stages.…”

“…Fungal development is usually accompanied by changes in enzyme activities (Zalokar, 1959;Nagasaki, 1968;Stine, 1969). A few mural exoenzymes in fungi are also present in amounts that vary with the age of the organism (Horikoshi & Ikeda, 1965;Mahadevan & Mahadkar, 1970).…”