Amperometrische Bestimmungen des Sulfhydrylgruppengehaltes tierischer Linsen

Thomann, H.

doi:10.1007/bf00689896

Cited by 9 publications

(3 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values for half-cystine, determined by automatic analysis, are also shown, although the accuracy of this method is known to be poor. The cysteine value obtained by amperometric titration was considerably higher than that reported by Firfarova & Levdikova (1961) and was in closer agreement with the values determined by Thomann (1958) and by Waley (1965).…”

Section: Sub-units Of A-crystallinsupporting

confidence: 90%

Further studies on the sub-units of α-crystallin

Wisse¹,

Zweers²,

Jongkind³

et al. 1966

Biochemical Journal

View full text Add to dashboard Cite

1. A new procedure is described for the purification of alpha-crystallin, including: preparative zone electrophoresis, density-gradient centrifugation and gel filtration. The total amino acid composition of highly purified samples prepared according to this procedure has been determined. 2. Evidence is presented for the presence of intermediates in the urea-induced splitting of alpha-crystallin into sub-units. A possible mechanism for this splitting is proposed. 3. The recombination of sub-units has been studied by polyacrylamide-gel electrophoresis and ultracentrifugal analysis. As judged from these criteria, only a partial recovery of starting material was obtained. 4. The origin of the minor bands in the electrophoretic pattern of alpha-crystallin on 7m-urea-polyacrylamide gel has been investigated. No evidence was found that their presence is due to carbamoylation or sulphide-disulphide interchange. They probably arise from isomerization. 5. The mean molecular weight of the sub-units was calculated to be 24000 (Archibald's method). Determination of the sedimentation-diffusion equilibrium revealed a value of 21000 at the meniscus. Assuming that all sub-units contain one cysteine residue/molecule, 23000 can be derived for the mean molecular weight.

show abstract

Section: Sub-units Of A-crystallinsupporting

confidence: 90%

Further studies on the sub-units of α-crystallin

Wisse¹,

Zweers²,

Jongkind³

et al. 1966

Biochemical Journal

View full text Add to dashboard Cite

show abstract

“…Sequence around the cysteine re8lklue8 in len8 protein8. Bovine ac-crystallin contains 1 cysteine residue/20 000 g. of protein (Thomann, 1959;Wisse et al 1966) and partial acid hydrolysis of the carboxymethylated protein gives Ser-CMOys (Waley, 1965a). This is a characteristic of bovine a-crystallin shared by human a-crystallin and by bovine and human albuminoid.…”

Section: Discussionmentioning

confidence: 99%

Structural studies on lens proteins

Mok¹,

Waley²

1967

Biochemical Journal

View full text Add to dashboard Cite

The sequence around the thiol group in lens proteins has been investigated. The proteins were converted into their carboxy[(14)C]methyl derivatives and submitted to partial acid hydrolysis, or digested with proteolytic enzymes. Acid hydrolysis of bovine alpha-crystallin gives N-seryl-(S-carboxymethyl)cysteine, Ser-CMCys (Waley, 1965a), but this dipeptide is not obtained from beta-crystallin or gamma-crystallin. Trypsin and chymotrypsin also give different peptides from the three crystallins. The radioactive peptide from alpha-crystallin and chymotrypsin has the sequence Ser-CMCys-Ser-Leu; another peptide, Asp-Leu-Leu-Phe, was also identified. The radioactive peptides obtained from bovine alpha-crystallin are probably also obtained from human alpha-crystallin, and from bovine and human albuminoid (the insoluble lens protein). alpha-Crystallin has been fractionated by chromatography in urea on DEAE-cellulose. Comparison of the fractions by peptide ;mapping', and immunochemically, shows that they fall into two classes. The fraction eluted first differs from the later fractions, but the later fractions resemble each other The first fraction may represent impurities, or it may be a structurally different sub-unit of alpha-crystallin.

show abstract

“…Bovine ac-crystallin contains 1 cysteine residue/20 000 g. of protein (Thomann, 1959;Wisse et al 1966) and partial acid hydrolysis of the carboxymethylated protein gives Ser-CMOys (Waley, 1965a). This is a characteristic of bovine a-crystallin shared by human a-crystallin and by bovine and human albuminoid.…”

Section: Discussionmentioning

confidence: 99%

Structural Studies on Lens Proteins

Mok¹,

Waley²

Biochemistry of the Eye

View full text Add to dashboard Cite

Amperometrische Bestimmungen des Sulfhydrylgruppengehaltes tierischer Linsen

Cited by 9 publications

References 17 publications

Further studies on the sub-units of α-crystallin

Further studies on the sub-units of α-crystallin

Structural studies on lens proteins

Structural Studies on Lens Proteins

Contact Info

Product

Resources

About