Table II.

Trehalase activity in yeast expressing AtTRE1 cDNA

Yeast Strain	Trehalase Activity at pH 4.5	Trehalase Activity at pH 6.3
	nkat mg−1 dry wt
YNM5 (+pAT)	10.0	6.53
YNM5 (+YcpAdh1)	<0.05	<0.05
YNM5	<0.05	<0.05

Trehalase activity in the following derivatives of the S. cerevisiae strain YNM5, lacking the ATH1 gene encoding acid trehalase: YNM5 (⁺pAT) (YNM5 transformed with the AtTRE1 expression plasmid pAT), YNM5 (untransformed mutant), and YNM5 (⁺YcpAdh1) (YNM5 transformed with YCpADH1; empty vector control). The cells had been grown to mid-log phase in liquid culture in synthetic dextrose minimal medium with the appropriate auxotrophic additions. Activity was measured at pH 4.5 and 6.3.