Literature summary for 4.2.1.22 extracted from

Singh, L.R.; Chen, X.; Kozich, V.; Kruger, W.D.
Chemical chaperone rescue of mutant human cystathionine beta-synthase (2007), Mol. Genet. Metab., 91, 335-342.

Cloned(Commentary)

Cloned (Comment)	Organism
expression of human mutant CBS proteins in Saccharomyces cerevisiae reveals that the disease causing mutation severely inhibits enzyme activity and cannot support growth of yeast on cysteine-free media. The osmolyte chemical chaperones glycerol, trimethylamine-N-oxide, dimethylsulfoxide, proline or sorbitol, when added to yeast media, allows growth on cysteine-free media and causes increased enzyme activity from I278T mutant protein. The increase in enzyme activity is associated with stabilization of the tetramer form of the enzyme. This effect is not specific to yeast, as addition of the chaperone glycerol results in increased I278T activity when the enzyme is produced either in Escherichia coli or in a coupled in vitro transcription/translation reaction. No stimulation of specific activity is observed when chaperones are added directly to purified I278T indicating that the presence of chemical chaperones is required during translation	Homo sapiens

Cloned (Comment)

Organism

expression of human mutant CBS proteins in Saccharomyces cerevisiae reveals that the disease causing mutation severely inhibits enzyme activity and cannot support growth of yeast on cysteine-free media. The osmolyte chemical chaperones glycerol, trimethylamine-N-oxide, dimethylsulfoxide, proline or sorbitol, when added to yeast media, allows growth on cysteine-free media and causes increased enzyme activity from I278T mutant protein. The increase in enzyme activity is associated with stabilization of the tetramer form of the enzyme. This effect is not specific to yeast, as addition of the chaperone glycerol results in increased I278T activity when the enzyme is produced either in Escherichia coli or in a coupled in vitro transcription/translation reaction. No stimulation of specific activity is observed when chaperones are added directly to purified I278T indicating that the presence of chemical chaperones is required during translation

Homo sapiens

Protein Variants

Protein Variants	Comment	Organism
A226T	mutant exhibits slight rescue with trimethylamine N-oxide and proline, but not glycerol, DMSO, or sorbitol	Homo sapiens
D376N	mutant is not rescuable by any of the chemical chaperones	Homo sapiens
G307S	mutant is not rescuable by any of the chemical chaperones	Homo sapiens
I278T	expression of human mutant CBS proteins in Saccharomyces cerevisiae reveals that the disease causing mutation severely inhibits enzyme activity and cannot support growth of yeast on cysteine-free media. The osmolyte chemical chaperones glycerol, trimethylamine-N-oxide, dimethylsulfoxide, proline or sorbitol, when added to yeast media, allows growth on cysteine-free media and causes increased enzyme activity from I278T mutant protein. The increase in enzyme activity is associated with stabilization of the tetramer form of the enzyme. This effect is not specific to yeast, as addition of the chaperone glycerol results in increased I278T activity when the enzyme is produced either in Escherichia coli or in a coupled in vitro transcription/translation reaction. No stimulation of specific activity is observed when chaperones are added directly to purified I278T indicating that the presence of chemical chaperones is required during translation	Homo sapiens
N228S	mutant is not rescuable by any of the chemical chaperones	Homo sapiens
Q526K	mutant is not rescuable by any of the chemical chaperones	Homo sapiens
T262M	expression of human mutant CBS proteins in Saccharomyces cerevisiae reveals that the disease causing mutation severely inhibits enzyme activity and cannot support growth of yeast on cysteine-free media. The osmolyte chemical chaperones glycerol, trimethylamine-N-oxide, dimethylsulfoxide, proline or sorbitol, when added to yeast media, allows growth on cysteine-free media and causes increased enzyme activity from I278T mutant protein. The increase in enzyme activity is associated with stabilization of the tetramer form of the enzyme. This effect is not specific to yeast, as addition of the chaperone glycerol results in increased I278T activity when the enzyme is produced either in Escherichia coli or in a coupled in vitro transcription/translation reaction. No stimulation of specific activity is observed when chaperones are added directly to purified I278T indicating that the presence of chemical chaperones is required during translation	Homo sapiens
T353M	expression of human mutant CBS proteins in Saccharomyces cerevisiae reveals that the disease causing mutation severely inhibits enzyme activity and cannot support growth of yeast on cysteine-free media. The osmolyte chemical chaperones glycerol, trimethylamine-N-oxide, dimethylsulfoxide, proline or sorbitol, when added to yeast media, allows growth on cysteine-free media and causes increased enzyme activity from I278T mutant protein. The increase in enzyme activity is associated with stabilization of the tetramer form of the enzyme. This effect is not specific to yeast, as addition of the chaperone glycerol results in increased I278T activity when the enzyme is produced either in Escherichia coli or in a coupled in vitro transcription/translation reaction. No stimulation of specific activity is observed when chaperones are added directly to purified I278T indicating that the presence of chemical chaperones is required during translation	Homo sapiens

Organism

Organism	UniProt	Comment	Textmining
Homo sapiens	-	-	-