Multiple Mannosyl Transferases in Cryptococcus laurentii

Mannosyl transfer in Cryptococcus laurentii.

A particle-bound enzyme from the fungus imperfectus Cryfitococcus taurentii var. flavescens (NRRL Y-1401) mediates transfer of mannosyl units from GDP-mannose to endogenous primer. The enzyme requires divalent cations for activity. The pH optimum is ‘7.5 and the apparent K, for GDP-mannose is 0.14 mbr. A polysaccharide fraction that is associated with the enzyme was found to be similar to a pol...

Xylosyltransferases in Cryptococcus laurentii.

Heteroglycan synthesis in Cryptococcus laurentii.

An enzyme preparation from Cryptococcus laurentii catalyzes the transfer of glycosyl units from sugar nucleotides to exogenous acceptor resulting in the stepwise synthesis of a heteroglycan with the following structure: Z-O-a-n-mannosyl6-O-oc-D-mannosyl-3-~-~-D-mannosyl-(2 -0 -0 -D -xylosyl-) D-mannose. The same enzyme preparation transfers D-[‘T]mannosyl from GDP [WJmannose to an endogenous gl...

Mannosyl Transfer in Cryptococcus Zuurentii*

A particle-bound enzyme from the fungus imperfectus Cryfitococcus taurentii var. flavescens (NRRL Y-1401) mediates transfer of mannosyl units from GDP-mannose to endogenous primer. The enzyme requires divalent cations for activity. The pH optimum is ‘7.5 and the apparent K, for GDP-mannose is 0.14 mbr. A polysaccharide fraction that is associated with the enzyme was found to be similar to a pol...

Phytase activity in Cryptococcus laurentii ABO 510.

Ten Cryptococcus strains were screened for phytase activity, of which the Cryptococcus laurentii ABO 510 strain showed the highest level of activity. The cell wall-associated enzyme displayed temperature and pH optima of 62 degrees C and 5.0, respectively. The enzyme was thermostable at 70 degrees C, with a loss of 40% of its original activity after 3 h. The enzyme was active on a broad range o...