Biologically active compounds of semi-metals
1Institute of Microbiology, Vídenská 1083, Prague 142 20, Czech Republic. rezanka@biomed.cas.cz
Phytochemistry
|November 10, 2007
Summary
Semi-metals like boron, silicon, arsenic, and selenium form organometallic compounds with significant biological roles. These compounds impact living organisms, with some metalloids like tellurium and astatine lacking biological relevance.
Area of Science:
- Biochemistry
- Environmental Science
- Toxicology
Background:
- Semi-metals (boron, silicon, arsenic, selenium) form organometallic compounds.
- Some organometallic compounds occur naturally and influence organism physiology.
- Tellurium and astatine are rare metalloids with no known biological significance.
Purpose of the Study:
- To review the biological significance of organometallic compounds formed by semi-metals.
- To highlight the diverse roles of boron, silicon, arsenic, and selenium in biological systems.
- To differentiate between biologically active and inactive metalloids.
Main Methods:
- Literature review of biochemical and microbiological studies.
- Analysis of natural product chemistry and metabolic pathways.
- Examination of toxicological and pharmacological data.
Main Results:
- Boron forms antibiotics (aplasmomycin, borophycin, boromycin, tartrolon).
- Silicon is released by bacteria (Bacillus relatives) from aluminosilicates.
- Arsenic is metabolized into arsenosugars, arsenobetaines, and volatile methylated compounds by various organisms.
- Selenium is incorporated into selenocysteine and used in drug analogues.
- Prokaryotes utilize arsenate and arsenite in energy metabolism.
Conclusions:
- Organometallic compounds of boron, silicon, arsenic, and selenium play crucial roles in biology.
- These semi-metals exhibit diverse biochemical functions, from antibiotic production to energy metabolism.
- Understanding these roles is vital for pharmacology and environmental science.
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