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The biology of mycorrhiza in the Ericaceae
Author(s) -
LEAKE J. R.,
READ D. J.
Publication year - 1989
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/j.1469-8137.1989.tb00310.x
Subject(s) - pepstatin , ericaceae , enzyme , mycorrhiza , biology , enzyme assay , extracellular , fungus , botany , biochemistry , ectomycorrhiza , symbiosis , bacteria , genetics , protease
SUMMARY Hymenoscyphus ericae utilizes protein as a sole source of nitrogen through the production of an extracellular proteinase. A sensitive procedure for assay of the enzyme is described and is used to determine the major characteristics of the enzyme. The enzyme has a sharp pH optimum at 2.2 with little activity above pH 5.0. Values for K m and V max of the enzyme were determined. Pepstatin, a specific inhibitor of carboxyl (acid) proteinases, almost completely inhibited activity, confirming that the enzyme is of this type. The characteristics of the enzyme are compared with those described for other microbial acid proteinases and the results are discussed in relation to physiological ecology both of the fungus and of its host plant.