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Updated: Jun 19, 2026
09:04
Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii
Published on: April 16, 2016
ON THE MECHANISM OF SPECIFIC PRECIPITATION.
1Evans Memorial, Massachusetts Memorial Hospitals, and Boston University School of Medicine, Boston.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Specific precipitation depends on reducing solubility, not lattice formation. Key factors include free polar groups on haptens and the distance between reactive sites, influencing steric hindrance.
Area of Science:
- Immunochemistry
- Biophysical Chemistry
Background:
- Specific precipitation is a fundamental immune assay.
- The role of antigen structure in precipitation has been debated.
- Previous models often emphasized lattice formation.
Purpose of the Study:
- To investigate the fundamental mechanisms driving specific precipitation.
- To determine the necessary and sufficient conditions for hapten-antibody precipitation.
- To elucidate the influence of hapten structure on precipitation.
Main Methods:
- Studied the precipitability of 34 different haptens with antisera.
- Varied haptens contained one to six reactive groups.
- Analyzed the relationship between hapten structure and precipitation.
Main Results:
- Framework (lattice) formation is neither necessary nor sufficient for precipitation.
- Precipitation is driven by reduced solubility of the antibody-hapten complex.
- Reduced solubility results from neutralization of polar groups and mechanical blocking.
- Free polar groups on haptens and inter-group distance are critical factors.
- Steric hindrance between antibody molecules influences precipitation.
Conclusions:
- Specific precipitation is primarily governed by solubility reduction, not solely by lattice formation.
- Hapten structure, specifically the number of free polar groups and their spacing, dictates precipitation.
- The findings challenge traditional views emphasizing lattice formation as the sole driver of precipitation.
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