2.3.2.13: protein-glutamine gamma-glutamyltransferase

the mutant binds to heparin with about wild type affinity

D94A/D97A

the mutant is found at comparable levels on the cell surface with that shown for the wild type enzyme

K205A/R209A

the mutant shows increased activity in NIH 3T3 and HEK-293/T17 cell lysates compared to the wild type enzyme

K60A/R601A/K602A

the mutant shows reduced activity in NIH 3T3 cell lysates and increased activity in HEK-293/T17 cell lysates compared to the wild type enzyme

C230A

the mutant shows about wild type activity but is less susceptible to oxidation than the wild type enzyme

719877

C277A

the mutant is unable to bind guanine nucleotides

C277S

C277V

the mutant is susceptible to digestion by trypsin, and significantly impaired in nucleotide binding

C370A

the kcat/Km is 33% of the wild type enzyme

719877

C371A

the kcat/Km is 5% of the wild type enzyme

719877

D151N/E153Q/E154Q/E155Q/E158Q

mutation of calcium binding site, does not cause major structural alterations. Mutant binds less than 6 Ca2+ and is deficient in transglutaminase activity. GTPase activity is activated by presence of Ca2+

D306N/N308S/N310S

mutation of calcium binding site, does not cause major structural alterations. Mutant binds less than 6 Ca2+ and is deficient in transglutaminase activity

D306N/N310A

the purified tTG mutant adopts a conformation similar to that of wild-type tTG, based on their mutual ability to bind bodipy-GTP-gammaS and to resist proteolysis by trypsin

D434A

the mutant can be transiently expressed in NIH 3T3 cells but not be generated as recombinant protein. The mutant is cytotoxic when expressed in NIH 3T3 cells

D434N/E435Q/E437N

E396Q/N398S/D400N

mutation of calcium binding site, does not cause major structural alterations. Mutant binds less than 6 Ca2+ and is deficient in transglutaminase activity

E447Q/E451Q/E452Q/E454Q

mutation of calcium binding site, does not cause major structural alterations. Mutant binds less than 6 Ca2+ and is deficient in transglutaminase activity

F174A

the F174A mutant is deficient in nucleotide binding, and is digested by trypsin in the presence of GTP-gammaS, Phe174 appears to be involved in a pi-stacking interaction

F174W

mutant resists proteolysis and is able to bind nucleotide

G224V

K677A

the mutant can be transiently expressed in NIH 3T3 cells but not be generated as recombinant protein, the mutant is unable to bind bodipy-GTP-gammaS, and shows high sensitivity to degradation by trypsin. The mutant is cytotoxic when expressed in NIH 3T3 cells

N229S/N231S/D232N/D233N

mutation of calcium binding site, does not cause major structural alterations. Mutant binds less than 6 Ca2+ and is deficient in transglutaminase activity

N681A

the mutant can be transiently expressed in NIH 3T3 cells and generated as recombinant protein. The mutant is cytotoxic when expressed in NIH 3T3 cells

Q163D

the mutant shows no loss of nucleotide binding ability when assayed with [alpha-32P] GTP, and exhibits only a moderate loss of binding ability when assayed with [35S]GTP-gammaS

Q163L

the mutant shows no loss of nucleotide binding ability when assayed with [alpha-32P] GTP, and exhibits only a moderate loss of binding ability when assayed with [35S]GTP-gammaS

Q164L

the mutant shows no loss of nucleotide binding ability when assayed with [alpha-32P] GTP, and exhibits only a moderate loss of binding ability when assayed with [35S]GTP-gammaS

Q169L

the mutant shows no loss of nucleotide binding ability when assayed with [alpha-32P] GTP, and exhibits only a moderate loss of binding ability when assayed with [35S]GTP-gammaS

R476A

the mutant binds nucleotide as well as the wild-type enzyme

R478A

the mutant has partially reduced nucleotide binding

R579A

the R579A mutant of tTG is far more susceptible to proteolysis by trypsin or by calpain than the wild-type

R580A

the mutant is GTP-binding deficient

R580K

decreases in nucleotide binding are observed for the R580L and R580K mutants

R580L

decreases in nucleotide binding are observed for the R580L and R580K mutants

R580L/C277A

the tTG mutant is deficient in GTP-binding and protein crosslinking activity, but still induces cell death

S171A

the mutant binds nucleotide as well as the wild-type enzyme

S216A

the mutant lacks the S216 phosphorylation site

719171

T360A

mutants show an increase in preference for deamidation with respect to transamidation compared to the wild-type enzyme

T360W

mutants show an increase in preference for deamidation with respect to transamidation compared to the wild-type enzyme

W241A

no detectable activity

W254A

the mutant can be transiently expressed in NIH 3T3 cells and generated as recombinant protein, the mutant is unable to bind bodipy-GTP-gammaS, and shows high sensitivity to degradation by trypsin. W254A forms a dimer of tTG molecules in the open-state conformation. The mutant is cytotoxic when expressed in NIH 3T3 cells

W332A

no detectable activity

Y516C

the mutant is less capable of binding guanine nucleotide compared to wild-type

Y516F

the mutant is less capable of binding guanine nucleotide compared to wild-type

C277A

the mutant lacks transamidation function

I331N

the mutant is associated with early-onset type 2 diabetes, has no GTP-binding ability and shows 32% of wild type activity

M330R

the mutant is associated with early-onset type 2 diabetes, has very weak GTP-binding ability and shows 20% of wild type activity

N333S

the mutant is associated with early-onset type 2 diabetes, has elevated GTP-binding ability and shows 7% of wild type activity

S216A