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E Stumm-Zollinger

Publications and source records attributed to E Stumm-Zollinger.

6 recordsLinked to original sources
PubMed1989

A male accessory gland peptide with protease inhibitory activity in Drosophila funebris.

Male accessory glands of Drosophila funebris synthesize and secrete a peptide that shows a protease-inhibiting activity. Amino acid sequencing of the purified peptide revealed that the peptide consists of 63 amino acid residues. It is a serine protease inhibitor belonging to the pancreatic trypsin inhibitor (Kunitz) family. The inhibitory function and the kinetic characteristics of the inhibition have been examined with various substrates. The peptide possibly plays a role as an acrosin inhibitor involved in Drosophila reproduction.

Amino Acid Sequence↗
PubMed1988

A male accessory gland peptide that regulates reproductive behavior of female D. melanogaster.

The adult male accessory glands of D. melanogaster synthesize and secrete a peptide that represses female sexual receptivity and stimulates oviposition. Normally, this peptide is transferred to females during copulation; however, the peptide shows the same biological activity after purification and subsequent injection into the abdominal cavity of female virgins. Amino acid sequencing of the purified peptide and oligonucleotide-directed cDNA cloning established that the peptide consists of 36 amino acids. It appears to be synthesized as a precursor with a hydrophobic signal sequence of 19 residues at its N-terminal end. The precursor peptide is encoded by a short mRNA that accumulates exclusively in the male accessory gland. The gene has been localized by in situ hybridization to polytene chromosomes at 70A.

Amino Acid Sequence↗
PubMed1983

The genes coding for 4 snRNAs of Drosophila melanogaster: localization and determination of gene numbers.

Four small nuclear RNAs (snRNAs) have been isolated from Drosophila melanogaster flies. They have been characterized by base analysis, fingerprinting, and injection into Axolotl oocytes. The size of the molecules and the modified base composition suggest that the following correlations can be made: snRNA1 approximately U2-snRNA; snRNA2 approximately U3-snRNA; snRNA3 approximately U4-snRNA; snRNA4 approximately U6-snRNA. The snRNAs injected into Axolotl oocytes move into the nuclei, where they are protected from degradation. The genes coding for these snRNAs have been localized by "in situ" hybridization of 125-I-snRNAs to salivary gland chromosomes. Most of the snRNAs hybridize to different regions of the genome: snRNA1 to the cytological regions 39B and 40AB; snRNA2 to 22A, 82E, and 95C; snRNA3 to 14B, 23D, 34A, 35EF, 39B, and 63A; snRNA4 to 96A. The estimated gene numbers (Southern-blot analysis) are: snRNA1:3; snRNA2:7; snRNA3:7; snRNA4:1-3. The gene numbers correspond to the number of sites labeled on the polytene salivary gland chromosomes.

Ambystoma↗
PubMed1966

Effects of inhibition and repression on the utilization of substrates by heterogeneous bacterial communities.

This investigation attempts to evaluate to what extent enzyme inhibition and repression by metabolites, indigenous to the cell, are significant phenomena in natural microbial communities. Three case histories of the kinetics of substrate utilization and growth in multisubstrate media by heterogeneous bacterial populations are presented: (i) concurrent substrate utilization and growth on both substrates simultaneously (glucose plus benzoate); (ii) sequential substrate elimination accompanied by diauxic growth as a result of inhibition of enzyme activity (glucose plus galactose); (iii) sequential substrate utilization accompanied by diauxic growth caused by repression of enzyme formation (glucose plus l-phenylalanine, benzoate plus l-phenylalanine). It is shown that enzyme inhibition was observed in two-substrate media as well as in multisubstrate media and was maintained at low substrate concentrations (few milligrams per liter). A special attempt has been made to maintain the diversity of the experimental microbial population during the adaptation and enrichment period. All substrates were determined with sensitive analytical methods specific for the individual substrates. The results obtained confirm that catabolite repression and the resulting sequential substrate utilization are observed in heterogeneous bacterial populations.

Acids↗