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J L Reissig

Publications and source records attributed to J L Reissig.

14 recordsLinked to original sources
PubMed1983

Calcium as a branching signal in Neurospora crassa.

The divalent cation ionophore A23187 was found to induce apical branching in Neurospora crassa. Optimal effects were obtained by treatment with 0.1 mM ionophore for 30 min. Branching first became manifest during or shortly after treatment; successive rounds of branching could be observed at later times. Calcium starvation of the mycelium markedly reduced its subsequent response to the ionophore, whereas starvation for other divalent cations had no detectable effect. The branching response was markedly reduced in the presence of 10 to 30 mM cyclic AMP or derivatives thereof.

Bucladesine↗
PubMed1982

Purification and characterization of Neurospora crassa N-acetyl galactosaminoglycan deacetylase.

1. N-Acetyl galactosaminoglycan deacetylase was purified from Neurospora mycelium 215-fold in 25% yield to electrophoretic homogeneity. A single band corresponding to a molecular weight of 76,000 was obtained by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. 2. The enzyme activity had pH optima at pH 5.0 and 9.0. Sodium molybdate, 2 mM, stimulated enzyme activity 4-fold at pH 5.0 but had no effect at pH 9.0. Cupric ion, 1 mM, inhibited activity by more than 85% at pH 5.0 and 9.0. The Km of the enzymatic reactions was 16 microM on the basis of the concentration of N-acetylgalactosamine. 3. This enzyme may be involved in determining the properties of the hyphal apex of the colonial form of Neurospora crassa and thus could play a role in morphogenetic regulation.

Amidohydrolases↗
PubMed1975

An endogalactosaminidase from Streptomyces griseus.

An endogalactosaminidase has been purified 34-fold from the culture filtrate of Streptomyces griseus. This enzyme cleaves GalN-GalN linkages in oligogalactosaminoglycan, a galactosamine-rich oligosaccharide isolated from the culture filtrate of a Neurospora mutant. Since some or all of the GalN-GalN bonds in this molecule link positions 1 and 4, and are in the alpha-configuration, we are probably dealing with an endo-alpha-(1 leads to 4)-galactosaminidase, bu this characterization is only tentative because the few bonds cleaved by the enzyme could have a different structure. The enzyme is inactive towards N-acetyl-oligogalactosaminoglycan and chitosan. The endogalactosaminidase preparations also cleave high molecular weight galactosaminoglycan (obtained from Neurospora) into fragments greater than or equal to 10(4) daltons in molecular weight, and catalyze the release of Neurospora sporelings from the glass surfaces to which they are anchored. Galactosaminoglycan-cleaving and sporeling-releasing activities elute jointly from DEAE-cellulose columns. This observation provides further support for an earlier proposal that the sporelings are anchored to the glass by means of galactosaminoglycan molecules.

Glycosaminoglycans↗
PubMed1974

Interaction of galactosaminoglycan with Neurospora conidia.

The inactivation of Neurospora crassa conidia by galactosaminoglycan isolated from cultures of this organism was followed by measuring colony-forming ability and ability to take up radiolabeled metabolites. When kinetic data on the loss of transport function and on killing were analyzed by use of target theory, it appeared that few "hits" are required for inactivation. However, studies with radio-labeled galactosaminoglycan mucopolysaccharides showed that cells receiving a single lethal hit have approximately 10(5) galactosaminoglycan molecules bound to them.

Absorption↗
PubMed1971

Mucopolysaccharide which regulates growth in Neurospora.

Neurospora produces a mucopolysaccharide (called MP) which inhibits its growth, causes vacuolation and agglutination of its cells, and precipitates its purified membrane protein. Cultures of a colonial strain display a phase of slow growth; the induction of this phase is traced to the production of MP by the mold. Stationary-phase cultures of wild type also produce MP. MP is a polymer of galactosamine, its amino groups only partially acetylated, probably containing other minor components. MP molecular weight is approximately 10(6). Complete acetylation abolishes the biological activities of MP. It is suggested that the regulatory effect of MP is mediated by its interaction with the protoplasmic membrane.

Agglutination↗