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T Kleinschmidt

Publications and source records attributed to T Kleinschmidt.

88 records · Page 5Linked to original sources

[The sequence of a dimeric haemoglobin (component VIIB, Chironomus thummi thummi, Diptera) (author's transl)].

The primary structure of the symmetric dimeric haemoglobin from type alpha2 component CTT VIIB from the larvae of Chironomus thummi thummi is given. The sequence revealed the presence of at least two components differing in six positions. A comparison with human alpha-chains is discussed with respect to the primary structure, helices, and haem complex and haem contacts.

Amino Acids↗

Separation of peptides on Empore thin-layer chromatography sheets and blotting onto polyvinylidene difluoride membranes with subsequent gas phase sequencing.

Methods for the separation of peptides on a new type of thin-layer chromatography (TLC) sheet and blotting onto polyvinylidene difluoride (PVDF) membranes with subsequent gas phase sequencing are described. For validation, the A and B chain of insulin were chromatographed on Empore TLC sheets and either extracted or blotted onto PVDF membranes. The advantages and disadvantages of thin-layer chromatography on Empore sheets versus high performance liquid chromatography (HPLC) are discussed, along with the possibility of combining the two methods. In addition, TLC was combined with electrophoresis (fingerprinting) for the separation of complex peptide mixtures. Blotting from TLC sheets onto PVDF membranes was performed in two ways: contact diffusion and electrophoretic transfer. In our experiments electroblotting was more effective. Amino acid sequence determination of the B chain of insulin was possible both after extraction from the TLC sheet and after blotting onto PVDF membranes. In the former case, liquid phase sequencing and, in the latter case, gas phase sequencing was performed. The possibility to blot from TLC sheets onto membranes, e.g. PVDF, may prove useful in many fields, for example in biochemistry, and in molecular and cell biology.

Amino Acid Sequence↗

[N-terminal sequence of a porphobilinogen synthase].

The N-terminal sequence of porphobilinogen-synthase (EC 4.2.1.24) from bovine liver up to position 44 is given. After tryptic hydrolysis two N-terminal peptides with identical amino acid composition were isolated in the ratio 1:1. One peptide was blocked whereas the other one started with methionine and showed the same primary structure which had been estimated by automatic degradation of the enzyme. Four of the eight subunits of PBG-S have free methionine as N-terminal amino acid whereas the other half is blocked.

Amino Acid Sequence↗