Novel Mutation Causing Derepression of Several Enzymes of Sulfur Metabolism in Neurospora crassa

AUTOR(ES)

Burton, Earl G.

RESUMO

A group of enzymes of sulfur metabolism (arylsulfatase, cholinesulfatase, and a number of others) are normally repressed in Neurospora crassa by an abundant supply of a “favored” sulfur source such as methionine or inorganic sulfate. A mutant called sconc was isolated in which the formation of each of these enzymes is largely or completely nonrepressible. The structural genes for three of these enzymes have been mapped; sconc is not linked to any of them. It is also not linked to cys-3, another gene which is involved in control of the same group of enzymes. Two alleles of the structural gene for arylsulfatase [ars+ and ars(UFC-220)] produce electrophoretically distinguishable forms of arylsulfatase. Heterokaryons with the constitution sconc ars+ + scon+ars(UFC-220) were prepared. These heterokaryons produce both forms of arylsulfatase under conditions of sulfur limitation, but produce only the wild-type (ars+) form under conditions of sulfur abundance. When the alleles of ars and scon are in the opposite relationship, only the ars(UFC-220) form of arylsulfatase can be detected under conditions of sulfur abundance. Thus the effect of the sconc mutation seems to be limited to its own nucleus. The implications of these findings are discussed.

Documentos Relacionados

• Mutation in Neurospora crassa Affecting Some of the Extracellular Enzymes and Several Growth Characteristics
• Regulation of a Sulfur-Controlled Protease in Neurospora crassa
• Regulation of Tryptophan Biosynthetic Enzymes in Neurospora crassa
• Regulation of thymidine metabolism in Neurospora crassa.
• Metabolism of pyrimidine deoxyribonucleosides in Neurospora crassa.