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Biomedical subjects

C S Fullmer

Publications and source records attributed to C S Fullmer.

At least 55 records · Page 3Linked to original sources
PubMed1982

Evidence for multiple effects of vitamin D3 on calcium absorption: response of rachitic chicks, with or without partial vitamin D3 repletion, to 1,25-dihydroxyvitamin D3.

The effects of vitamin D3 or 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], or both, on the relationship among calcium absorption, vitamin D-induced calcium-binding protein (CaBP), and phospholipid metabolism were examined. When 1,25(OH)2D3 was injected intracardially into D3-deficient chicks, both the stimulation of calcium absorption and the induction of the synthesis of CaBP occurred 2-4 hr later. When 1,25(OH)2D3 was injected into chicks partially repleted with D3, an earlier increase in calcium absorption was observed without a significant change in the concentration of CaBP already present in the duodenal mucosa. Other early events were an increased uptake of calcium by the intestinal tissue and an alteration in phospholipid metabolism. These and other observations support the proposal that at least two phases of calcium absorption are influenced by 1,25(OH)2D3--permeation of calcium across the brush border, and transfer of calcium through and out of the cell. The first phase responds more rapidly to 1,25(OH)2D3 than does the second phase, correlates with changes in phospholipid metabolism, and might not be dependent on de novo protein synthesis. The second phase correlates with CaBP synthesis and therefore is dependent on protein synthesis. Either the first phase or the second phase can constitute the limiting step in calcium absorption.

Alkaline Phosphatase↗
PubMed1981

The amino acid sequence of bovine intestinal calcium-binding protein.

The complete amino acid sequence of the vitamin D-dependent bovine intestinal calcium-binding protein (minor A component) has been determined: Lys-Ser-Pro-Glu-Glu-Leu-Lys-Gly-Ile-Phe-Glu-Lys-Tyr-Ala-Ala-Lys-Glu-Gly-Asp-Pro-Asn-Gln-Leu-Ser-Lys-Glu-Glu-Leu-Lys-Leu-Leu-Leu-Gln-Thr-Glu-Phe-Pro-Ser-Leu-Le u-Lys-Gly-Pro-Ser-Thr-Leu-Asp-Glu-Leu-Phe-Glu-Glu-Leu-Asp-Lys-Asn-Gly-Asp-Gly-Glu-Val-Ser-Phe-Glu-Glu-Phe-Gln-Val-Leu-Val-Lys-Lys-Ile-Ser-Gln-OH. It is a 75-residue protein (computed Mr = 8501), contains a single Tyr, and is devoid of Cys, Met, Trp, His, and Arg. The bulk of the sequence was determined by automated sequencing of: (i) the intact protein for 20 cycles; (ii) a large N-bromosuccinimide peptide for 37 cycles; (iii) a tryptic peptide (29 cycles), isolated by high performance liquid chromatography. Also described is a highly sensitive and rapid procedure for peptide mapping by high performance liquid chromatography.

Amino Acid Sequence↗
PubMed1980

Effect to cholecalciferol and 1,25-Dihydroxycholecalciferol on the intestinal absorption of zinc in the chick.

The effect of cholecalciferol on the intestinal absorption of 65Zn was assessed in zinc-deficient and zinc-replete rachitic chicks, using the in situ ligated loop techniques. Cholecalciferol did not significantly affect 65Zn absorption in either group, although the synthesis of the intestinal calcium-binding protein (CaBP) in both groups was similar. In an analogous study, 1,25-dihydroxycholecalciferol increased 47Ca absorption and induced the synthesis of CaBP but exerted on effect on 65Zn absorption in zinc-deficient rachitic chicks. When fed a diet adequate in cholecalciferol, more CaBP was present in the intestine of the zinc-adequate group than in the zinc-deficient group, possibly due to the greater rate of growth and therefore the greater need for calcium by the former group. These results suggest that cholecalciferol and its most active metabolite do not directly affect zinc absorption and, by inference, that the vitamin D-dependent transport mechanism is not involved in zinc homeostasis, or in the interaction between calcium and zinc.

Animals↗
PubMed1979

Analytical peptide mapping by high performance liquid chromatography. Application to intestinal calcium-binding proteins.

Peptide mapping of underivatized tryptic digests of bovine and chick intestinal calcium-binding proteins has been accomplished by high performance liquid chromatography (HPLC). High precision analysis of nanomolar quantities of peptides were achieved in less than 1 h (recycle time). Peak resolution and definition are superior compared to conventional techniques and recoveries of both small (4-residue) hydrophilic and large (30-residue) hydrophobic peptides are excellent. The total amino acid composition of the bovine intestinal calcium-binding protein has been accounted for on the basis of two tryptic maps of 20 microgram of protein each.

Amino Acids↗
PubMed1978

Microcapsule of Campylobacter fetus: chemical and physical characterization.

The antiphagocytic antigen (antigen [a]) comprising the microcapsule of a strain of Campylobacter fetus subsp. intestinalis has been purified from culture supernatants by ammonium sulfate fractionation and free-flow electrophoresis. Antigen [a] is a glycoprotein containing about 4% carbohydrate consisting of hexose, pentose, and methylpentose. The composition of the protein was typical of bacterial extramural structural proteins in its low content of basic, aromatic, and sulfur-containing amino acids. The protein had a high content of aspartic acid, threonine, glycine, and alanine. Antigen [a] had an Rf of 0.33 on polyacrylamide gel electrophoresis and a molecular weight calculated in sodium dodecyl sulfate-polyacrylamide gel electrophoresis of approximately 98,000. In contrast to its free form in culture supernatants, antigen [a] in vesicles derived from sheared cells appeared to exist in a complex with lipopolysaccharide. This complex could be dissociated by ethylenediaminetetraacetic acid or by ethylenediaminetetraacetic acid plus Triton X-100. A mutant strain that lacked a microcapsule, when incubated with soluble antigen [a] in a calcium medium, became agglutinable by monospecific [a] antiserum and showed an additional structural layer similar in appearance to the microcapsule on its cell wall. Points of similarity are emphasized between antigen [a] of C. fetus and the outer structural protein of the taxonomically related Spirillum serpens.

Agglutination↗
PubMed1976

The purification of calcium-binding protein from the uterus of the laying hen.

Calcium-binding proteins from the chick intestine and uterus of the laying hen (Gallus domesticus) were isolated and purified by identical methods. Proteins from each source were shown to exhibit identical electrophoretic mobility and were immunologically identical. Estimation of molecular size by gel filtration indicated a value of approximately 28,000 daltons for both the chick intestinal and hen uterine calcium-binding proteins. The amino acid compositions of chick intestinal and hen uterine calcium-binding proteins were essentially identical.

Amino Acids↗
PubMed1975

The effect of calcium on the tryptic digestion of bovine intestinal calcium-binding protein.

The tryptic hydrolysis of bivine intestinal calcium-binding protein in the presence and absence of excess calcium has been investigated. Calcium-binding activity and immunological reactivity of the protein were not significantly affected in the presence of 1.0 mM CaCl2 following 24 h incubation at 38 degrees C with trypsin at ratios of 1:9 of enzyme to calcium-binding protein. Some modification of the protein did occur under these conditions, however, since analysis by analytical acrylamide gel electrophoresis indicated the formation of a more rapidly-migrating species from the slower-moving original protein band. Omission of added calcium from the incubation medium resulted in rapid and essentially complete destruction of calcium-binding activity and immunological reactivity, and the formation of peptides of low molecular weight. This provides evidence that the conformation of the calcium-binding protein in the presence of calcium differs from that in its absence.

Animals↗
PubMed1975

Isolation and partial characterization of intestinal calcium-binding proteins from the cow, pig, horse, guinea pig, and chick.

1. Intestinal calcium-binding proteins have been isolated in high purity from mucosal tissue of the cow, pig, horse, guinea pig, and chick. The proteins from all species exhibit rapid, although not identical, electrophoretic mobilities and possesses high affinities for calcium. 2. The intestinal calcium-binding proteins of mammalian origin exhibit a molecular size of approx. 11 000 by calibrated gel filtration and 9000 on the basis of amino acid composition. The analogous chick protein was found to be about 27 000-28 000 molecular weight by these methods. 3. The amino acid composition of each intestinal calcium-binding protein has been determined and indicates a considerable degree of similarity, especially among the mammalian species. 4. Immunoassay procedures have failed to show any species cross-reactivity when tested against antiserum prepared in response to either the bovine or chick intestinal calcium-binding protein.

Amino Acids↗