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F Lottspeich

Publications and source records attributed to F Lottspeich.

At least 397 records · Page 22Linked to original sources

Novel opioid peptides derived from casein (beta-casomorphins). II. Structure of active components from bovine casein peptone.

Material with opioid activity had been isolated from an enzymatic casein digest. It was shown to contain a pure heptapeptide with the sequence Tyr-Pro-Phe-Pro-Gly-Pro-Ile. The identity between the opioid principle and the peptide was proven by the fact that chemical reagents or enzymes effecting one would effect the other. After carboxypeptidase Y digestion a pentapeptide, Tyr-Pro-Phe-Pro-Gly, could be isolated; this peptide showed a higher opioid activity than the heptapeptide. The opioid peptides were highly resistant towards proteolysis, even by pronase. The sequence of the hepatapeptide identified it as a fragment of bovine beta-casein. Therefore it was named beta-casomorphin.

Amino Acid Sequence↗

Carbohydrate linkage site in the beta-chain of human fibrin.

The beta-chain of fibrin was cleaved with trypsin or cyanogen bromide. Carbohydrate containing fragments were isolated by affinity chromatography on concanavalin A-agarose. The fragments were analysed for amino acid sequence and for amino and carbohydrate composition. The sequence of 21 amino acid residues around the carbohydrate attachment point was determined. The carbohydrate carrying amino acid was identified as aspartic acid/asparagine.

Amino Acid Sequence↗

Analysis of cerebrospinal fluid from patients with psychiatric and neurological disorders by two-dimensional electrophoresis: identification of disease-associated polypeptides as fibrin fragments.

Two-dimensional electrophoresis (2-DE) of cerebrospinal fluid (CSF) samples--from 347 patients with various psychiatric and neurological disorders--and subsequent silver staining revealed two additional polypeptides (Mr 40,000) in 49% of 111 schizophrenics, 46% of 43 schizoaffective patients, 36% of 41 patients with affective disorders, 43% of 28 patients with multiple sclerosis, but not in 25 patients without neurological symptomatology, nor in 9 patients with Lues, and in only 2 of 25 patients with AIDS. The two polypeptides, as detected by 2-DE, eluted after size exclusion chromatography in fractions containing proteins with Mr greater than 200,000. After 2-DE of CSF samples, enriched by gel chromatography, the polypeptides were immobilized by blotting onto glass-fiber membranes and subjected to N-terminal sequencing. Polypeptide A was identified as beta-chain remnant (beta 2), derived from plasmin cleavage of fibrin(ogen). After size exclusion chromatography, 2-DE, and Western blotting, polypeptide A and B, as well as several other spots, reacted with fibrinogen antibodies, suggesting that the polypeptides are subunits of a fibrin degradation complex.

Acquired Immunodeficiency Syndrome↗

Chromosomal localization of the HYP2-gene in Saccharomyces cerevisiae and use of pulsed-field gel electrophoresis for detection of irregular recombination events in gene disruption experiments.

In the hypusine-containing protein (HP), a specific lysine residue is modified by spermidine to form the unusual amino acid hypusine (4-amino-2-hydroxybutyllysine). The HP has been designated as an eucaryotic translation initiation factor--eIF-5A--because of its stimulating effect in the methionyl-puromycin in vitro assay. Nevertheless, the precise function of this protein remains to be elucidated. In the yeast Saccharomyces cerevisiae two genes, HYP1 and HYP2, coding for two different forms of the HP, are present. The HYP1-gene is identical to the ANB1-gene and has already been localized on chromosome X. However, the chromosomal localization of the HYP2-gene has not been elucidated. By using pulsed-field gel electrophoresis (PFGE) and subsequent Southern blotting, we determined the localization of the HYP2-gene to chromosome V. Furthermore, PFGE was used for the detection of irregular recombination events, such as misintegration or integration into a duplicated gene, and in gene disruption experiments using haploid and diploid yeast cells. The obtained data support the critical role of the HP for cell viability.

Chromosome Mapping↗