Biomedical subjects

K M Conn

Publications and source records attributed to K M Conn.

3 recordsLinked to original sources

PubMed1989

Monoclonal antibodies against osteonectin show conservation of epitopes across species.

Several monoclonal antibodies were produced to bovine osteonectin, a major noncollagenous protein in the extracellular matrix of bone, and four were characterized. These antibodies showed different reactivities in Western immunoblots, immunoprecipitation, and indirect immunofluorescence, indicating that they recognize different epitopes on the protein. The data indicate that an epitope recognized by one of the antibodies is masked in interactions of osteonectin within cells and in the extracellular matrix. The high degree of cross-species immunoreactivity observed against bone osteonectin with these monoclonal antibodies indicates that these common epitopes have been conserved during evolution.

Animals↗

PubMed1979

Enamel matrix: structural proteins.

Cell-free, fetal bovine enamel tissue was examined intact by high resolution. 13C Fourier transform, nuclear magnetic resonance spectroscopy. Two types of protein chains were observed under these conditions, one exhibiting rapid mobility and accounting for approximately two-thirds of the enamel matrix, while the other exhibited restricted or anisotropic segmental motion and accounted for the remaining third of the matrix. Sequential extraction of this fetal enamel under non-degradative conditions with dissociative solvents yielded two biochemically distinct populations of matrix protein. As expected, the bulk of the matrix consisted of proline-rich amelogenins, although the SDS-gel electrophoresis molecular weights for these proteins were somewhat higher than those reported using other extraction methods. Approximately fifteen percent of the total matrix consisted of much higher molecular weight phosphoproteins (46,000-72,000 daltons) whose amino acid composition closely resembled that reported for mature enamel protein. These high molecular weight proteins were tightly bound to the fetal enamel apatite crystallites.

Animals↗

PubMed1976

Inhibition of apatite formation by phosphorylated metabolites and macromolecules.

Apatite formation from synthetic extracellular fluids is rate-limited both at the initial amorphous precursor deposition step and at the amorphous-crystalline transformation reaction. Nucleotide diphosphates and triphosphates and low molecular weight metabolites containing two attached ester phosphate groups all inhibited amorphous-crystalline conversion at concentrations of 10(-5) to 10(-6)M. Both native and synthetic polynucleotides as well as the phosphoproteins from rat dentin or egg yolk also inhibited crystal formation from amorphous calcium phosphate. In all cases, substantial amounts of inhibitor molecules were incorporated into the stabilized amorphous precipitates. Treatment of isolated, inhibitor-stabilized amorphous precipitates with hydrolytic enzymes such as alkaline phosphatase or papain reversed the inhibitory effect and permitted crystallization to proceed normally.

Alkaline Phosphatase↗