Genetic and biochemical studies on cell-bound alpha-amylase in Bacillus subtilis Marburg.
A small but significant amount of alpha-amylase activity was detected in the cells of Bacillus subtilis Marburg. The cell-associated activity was almost constant regardless of the level of extracellular alpha-amylase activity. The cell-bound amylase activity could be separated into three components, upon Sephadex G-75 chromatography, referred to as components A, B, and C. Component C showed the same properties as the extracellular alpha-amylases so far examined. Component A had a molecular weight greater than 70,000, as judged from the elution position on Sephadex G-75, and became smaller upon treatment with trypsin but was still larger than that of component C. An alpha-amylase mutant that lacked extracellular alpha-amylase completely because of a mutation within the structural gene of the enzyme was found to lose all three cell-bound amylase components simultaneously. These data suggest strongly that the cell-bound amylase components are precursors of the extracellular alpha-amylase and that the alpha-amylase of this organism is produced under the direction of the same gene whether the enzyme is within or outside the cell.
D000681:Amylases / Q000302:isolation & purification / Q000378:metabolism*; D001412:Bacillus subtilis / Q000201:enzymology*; D002845:Chromatography; D002874:Chromosome Mapping; D005796:Genes; D005809:Genes, Regulator; D008970:Molecular Weight; D009154:Mutation; D014357:Trypsin / Q000494:pharmacology
D000681:Amylases; D014357:Trypsin