. "Any process that stops, prevents, or reduces the frequency, rate or extent of ubiquitin ligase activity, the catalysis of the reaction: ATP + ubiquitin + protein lysine = AMP + diphosphate + protein N-ubiquityllysine." . . . . "APC inhibitor" . "negative regulation of ubiquitin-protein ligase activity" . "anaphase promoting complex inhibition" . "anaphase promoting complex inhibitor" . "anaphase-promoting complex inhibition" . "anaphase-promoting complex inhibitor" . "APC inhibition" . "down regulation of ubiquitin ligase activity" . "down-regulation of ubiquitin ligase activity" . "downregulation of ubiquitin ligase activity" . "inhibition of ubiquitin ligase activity" . "negative regulation of ubiquitin ligase activity" . "SCF complex inhibitor" . "ubiquitin ligase inhibitor" . . . . .