Ascorbic acid oxidase of Myrothecium verrucaria

Copper Oxidases in Thalli of the Liverwort Marchantia polymorpha

“…On the contrary, the shape and tbe change in tbe slope of the curves indicate tbat zero order effects predominated when iiiilial substrate concentrations were low witb respect to Km, but Ibat higher order effects developed wben substrate concentrations increased. Tbe <levelopment of tbe higher order effects can possibly be ascribed to reaction inactivation as bas been put forward by Wbite and Smitb (35). The reaction rates rapidly fell off when the oxygen tension was lowered below 20 per The soluble proteins contained a powerful catecbolase, consuming balf a mole of oxygen for tbe oxidation of a mole of catechol.…”

“…In the soluble mycelial ascorbic acid oxidase from Myroihecium, a bigh degree of inhibition resistance was ob.served at pH 4.5 (35), whereas Ihe enzyme extracted from Phif. 'ianim polyeephalum (32) was greatly stimulated at pH 7.2 by mitinte amounts of DDC.…”

“…For Mijrotbecium verriicaria (35) and Physarum polyeephalum (32), it was cxi)licitly stated that the ascorbic acid oxidases were not accompanied by pbenolases.…”

“…Ascorbic acid oxidases which behave atypically in this respect however bave first been reported from Ihe spores of the fungtis yfgrotheeium rcrnicaria by Mandels (17) and from the slime mold Physaruin pohjecphdlum hy Ward (32). Recently, White and Smith (35) have shown that the properties of ascorbic Phmiol. Plant.. 20.…”

Properties of the ascorbic acid oxidase of Myrothecium verrucaria in vivo

“…The atypical ascorbic acid oxidase in Myrothecium verrucaria is reported to have somewhat different properties in spores than in mycelium (37,38,63,64). This was based on differences in pH activity response and substrate specificity between the extracted nycelial enzyme and the spore enzyme ex tracted or in intact spores.…”