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Collection of Post-mating Semen from the Female Reproductive Tract and Measurement of Semen Liquefaction in Mice
Published on: November 18, 2017
Structural properties of semenogelin I.
Johan Malm1, Magnus Jonsson, Birgitta Frohm
1Department of Laboratory Medicine, Section for Clinical Chemistry, Lund University, Malmö University Hospital, Sweden.
The FEBS Journal
|August 8, 2007
Summary
Semenogelin I, a key protein in semen, undergoes structural changes upon zinc binding. These alterations in tertiary structure may explain its role in gel formation.
Area of Science:
- Biochemistry
- Structural Biology
- Protein Chemistry
Background:
- Semenogelin I is the primary structural protein responsible for semen coagulum formation.
- It is characterized by a rapidly evolving structure with six repetitive units.
Purpose of the Study:
- To investigate the secondary and tertiary structural characteristics of semenogelin I.
- To explore the impact of zinc (Zn2+) binding on semenogelin I conformation.
- To understand the role of these structural changes in the protein's gel-forming ability.
Main Methods:
- Circular dichroism (CD) spectroscopy (far-UV and near-UV).
- Trp fluorescence emission spectroscopy.
- Temperature-dependent structural analysis (5-90°C).
Main Results:
- Semenogelin I secondary structure consists of 5-10% alpha-helix and 20-30% beta-sheet.
- The secondary structure is temperature-dependent.
- Zinc binding did not alter secondary structure but induced tertiary structure rearrangements, evidenced by changes in the near-UV CD spectrum.
Conclusions:
- Zinc binding induces conformational changes in semenogelin I's tertiary structure.
- These Zn2+-induced structural alterations are likely crucial for semenogelin I's gelation properties.
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