Substitution of alanine543 with a threonine residue at the carboxy terminal end of the beta-chain is associated with thermolabile hexosaminidase B in a Jewish family of Oriental ancestry.
Thermolabile forms of the lysosomal enzyme beta-hexosaminidase B (Hex B), likely to result from different genetic defects, have been described. Ten individuals in five generations of a family of Oriental Jewish ancestry were identified biochemically as carriers of a thermolabile Hex B form. The beta-chain thermolability was found to be associated with the presence of a G --> A transition at nucleotide 1627 of the HEX B gene causing the substitution of Ala543 with a threonine. Oriental Jew whose Hex B was heat labile. Since thermolabile Hex B has been shown to occur more frequently among Jews of Oriental origin, the Ala543 --> Thr mutation may be the common mutation associated with beta-chain thermolability in this ethnic group.
De Gasperi
R
R
Department of Neurology, New York University School of Medicine, New York 10016, USA.
Gama Sosa
M A
MA
Grebner
E E
EE
Mansfield
D
D
Battistini
S
S
Sartorato
E L
EL
Raghavan
S S
SS
Davis
J G
JG
Kolodny
E H
EH
D000409:Alanine / Q000737:chemistry*; D001483:Base Sequence; D002852:Chromatography, Ion Exchange; D005091:Exons; D005260:Female; D005347:Fibroblasts / Q000201:enzymology; D054819:Hexosaminidase B; D006358:Hot Temperature; D006801:Humans; D007492:Iran; D007585:Jews / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D010375:Pedigree; D011489:Protein Denaturation; D013912:Threonine / Q000737:chemistry*; D001619:beta-N-Acetylhexosaminidases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
D013912:Threonine; D054819:Hexosaminidase B; D001619:beta-N-Acetylhexosaminidases; D000409:Alanine