5.4.99.B22 D112A inactive mutant enzyme 682834 5.4.99.B22 D146A site-directed mutagenesis of truncated enzyme mutant DELTAhPus1p, differences between structures of DELTAhPus1p and DELTAhPus1pD146A are limited to external, poorly conserved loops, which confirm the flexibility of these regions 749148 5.4.99.B22 additional information generation of a truncated hPus1p version encompassing residues 83-394, i.e. DELTAhPus1p. The deleted N- and C-termini are not essential for either the RNA binding or the activity of the hPus1p enzyme 749148 5.4.99.B22 additional information generation of gene deletion mutant DELTApus1. which shows a U2 snRNA modification pattern identical to its parental wild-type strain ED666 -, 749279 5.4.99.B22 additional information generation of Pus1 knockout mice 749279 5.4.99.B22 additional information SNORA71 is expressed in an enzyme knockout mutant yeast strain, but do not restore pseudouridylation of the endogenous yeast U2 snRNA 749279 5.4.99.B22 R116A the mutant exhibits some activity with the yeast pre-tRNAIle substrate. Low activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116C the activity of the mutant enzyme with the yeast pre-tRNAIle substrate is approximately one-third that of the wild-type levels. No activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116E the mutant is inactive with with the yeast pre-tRNAIle substrate. No activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116G the mutant exhibits some activity with the yeast pre-tRNAIle substrate. No activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116H the mutant is inactive with with the yeast pre-tRNAIle substrate. Low activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116K the activity of the mutant enzyme with the yeast pre-tRNAIle substrate is approximately one-third that of the wild-type levels 695106 5.4.99.B22 R116N the mutant exhibits some activity with the yeast pre-tRNAIle substrate. No activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116Q the mutant exhibits some activity with the yeast pre-tRNAIle substrate. No activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116S the mutant exhibits some activity with the yeast pre-tRNAIle substrate. No activity with the mouse tRNAMet substrate 695106 5.4.99.B22 R116W the mutant is inactive with with the yeast pre-tRNAIle substrate. Low activity with the mouse tRNAMet substrate 695106 5.4.99.B22 Y173C mutant enzyme retains some activity with yeast pre-tRNAIle. The activity is relatively low 695106 5.4.99.B22 Y173F mutant enzyme is minimally activity with yeast pre-tRNAIle 695106 5.4.99.B22 Y173F mutant enzyme retains some activity with yeast pre-tRNAIle. The activity is relatively low 695106 5.4.99.B22 Y173G mutant enzyme retains some activity with yeast pre-tRNAIle. The activity is relatively low 695106 5.4.99.B22 Y173S mutant enzyme is minimally activity with yeast pre-tRNAIle 695106 5.4.99.B22 Y173T mutant enzyme is minimally activity with yeast pre-tRNAIle 695106 5.4.99.B22 Y173T mutant enzyme retains some activity with yeast pre-tRNAIle. The activity is relatively low 695106