Literature summary extracted from
Levinger, L.; Hopkinson, A.; Desetty, R.; Wilson, C.
Effect of changes in the flexible arm on tRNase Z processing kinetics (2009), J. Biol. Chem., 284, 15685-15691.
Cloned(Commentary)
EC Number |
Cloned (Comment) |
Organism |
---|
3.1.26.11 |
tRNase Z cDNA baculovirus-expressed from methionine 24 in insect Sf-9 cells |
Drosophila melanogaster |
Protein Variants
EC Number |
Protein Variants |
Comment |
Organism |
---|
3.1.26.11 |
DELTAFA |
deletion of the flexible arm (FA) hand close to its boundaries with the stalk does not interfere with stability and expression of tRNase ZL. DELTAFA hand variant has a Km ca. 100times higher and a kcat ca. 2times lower than wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
G196A/Pro201A |
increases in Km as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
G200A |
significant reductions in kcat as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
G209A |
increases in Km as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
I212A |
increases in Km as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
K207A |
increases in Km as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
K207A |
significant reductions in kcat as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
K214A/Lys218A |
significant reductions in kcat as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
L187A |
substitution of alanine causes Km to increase almost as much as deletion of the entire flexible arm hand, with barely any decrease in kcat. A higher concentration of L187A enzyme than that of wild-type tRNase Z has to be used to accommodate the lower catalytic efficiency of the variant |
Drosophila melanogaster |
3.1.26.11 |
L206A |
increases in Km as compared to wild-type tRNase Z |
Drosophila melanogaster |
3.1.26.11 |
additional information |
a conserved leucine at the ascending stalk/hand boundary causes practically the same increase in Km as the hand deletion, thus nearly eliminating its ability to bind substrate. Km also increases with substitutions in theGP(alpha4-alpha5) loop and at other conserved residues in the flexible arm hand predicted to contact substrate. Substitutions that reduce kcat are clustered in the beta10-beta11 loop |
Drosophila melanogaster |
Organism
EC Number |
Organism |
UniProt |
Comment |
Textmining |
---|
3.1.26.11 |
Drosophila melanogaster |
Q8MKW7 |
- |
- |
Purification (Commentary)
EC Number |
Purification (Comment) |
Organism |
---|
3.1.26.11 |
nickel chelate affinity purification of soluble tRNase Z |
Drosophila melanogaster |
Synonyms
EC Number |
Synonyms |
Comment |
Organism |
---|
3.1.26.11 |
tRNase Z |
- |
Drosophila melanogaster |
General Information
EC Number |
General Information |
Comment |
Organism |
---|
3.1.26.11 |
physiological function |
flexible arm of tRNase Z consists of 3540 residues in a globular, compact alphaalphabetabetaeta structure (the hand) extruded from the body of the enzyme and held apart from it by an extended two-stranded polypeptide stalk |
Drosophila melanogaster |