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D Bucher

Publications and source records attributed to D Bucher.

70 records · Page 4Linked to original sources
PubMed1979

Amino terminal sequence of hog intrinsic factor.

1. Hog intrinsic factor has been purified from gastric mucosa by labile ligand affinity chromatography. 2. The following N-terminal amino acid sequence has been determined: Thr-Arg-Ser-Ser-Cys-Ser-Val-Pro-Ser-Ala-Glu-Gln-Pro-Leu-Val-Asn-Gly-Ile- Gln-Val - Leu-Met. 3. However, approx 60% of the preparation lacked the first two residues. 4. A high degree of homology between the amino terminal sequence of human and hog intrinsic factor exists.

Amino Acid Sequence↗
PubMed1978

Primary structure of human intrinsic factor: progress report on cyanogen bromide fragmentation.

Human intrinsic factor purified by labile ligand affinity chromatography was cleaved with cyanogen bromide and fractionated by gel filtration. Four of the fragments were purified and sequenced to a total of eighty-four amino acid residues. Including the N-terminal amino acids this amounts to one third of the total amino acid sequence of human intrinsic factor. One of the fragments contained a tyrosine labelled only on iodination of intrinsic factor devoid of cobalamin.

Amino Acid Sequence↗
PubMed1977

Purification and characterization of rabbit transcobalamin II.

Rabbit transcobalamin II has been purified by labile ligand affinity chromatography and G-200 Sephadex gel filtration. Structural studies indicate Stokes' radii of 2.7 nm and 3.0 nm for transocobalamin II saturated and unsaturated with cobalamin. The amino acid content of the protein is very similar to that of human transcobalamin II (Allen, R. H. (1975) Prog. Hematol. 9, 59-84). The aminoterminal sequence for transcobalamin II is reported for the first time: Glu-Ile-Cys-Gly-Val-Pro-Lys-Val-Asp-Ser-Glu-Leu-Val-Glu-Lys-Leu-Gly-Gln-Arg-Leu-Leu-Pro-(Trp)-Met-Thr). The ultraviolet and circular dichroic spectra of aquo-, hydroxo-, azido- and cyanocobalamin bound to rabbit transcobalamin II are described. On complex formation the molar absorption of the cobalamins increases and the major bands shift to longer wavelengths. The spectra are little affected by change in the fifth ligand, which indicates that the electron density around the cobalt atom is kept fairly constant by the transcobalamin II molecule. This is in contrast to the observations for the same cobalamins attached to human intrinsic factor and human transcobalamin I (Nexo, E. and Olesen, H. (1976) Biochim. Biophys. Acta 446, 143-150).

Amino Acid Sequence↗
PubMed1976

An improved procedure for automated Edman degradation used for determination of the N-terminal amino acid sequence of human transcobalamin I and human intrinsic factor.

An improved procedure for automated Edman degradation is presented. Three programs are described, one with double cleavage and two with single cleavage. The programs presented are characterized by a reversed delivery scheme for buffer and phenyl isothiocyanate, and by reduced cleavage times. The modified procedures applied on automated Edman degradation of the vitamin B12-binding proteins human transcobalamin I and human intrinsic factor, containing approximately 390 and 350 amino residues respectively, gave the following N-terminal amino acid sequences: Human transcobalamin I Glu-Ile-Cys-Glu-Val-Ser-Glu-Glu-Asn-Tyr-Ile-Arg-Leu-Lys-Pro-Leu-Leu-Asn-Thr-Met-Ile-Gln-Ser-Asn-Tyr-Asn-?-Gly- Human intrinsic factor Ser-Thr-Gln-Thr-Gln-Ser-Ser-Cys-Ser-Val-Pro-Ser-Ala-Gln-Glu-Pro-Leu-Val-Asn-Gly-Ile-Gln-?-Leu-Met-Glu-Thr- The background accumulation seems to be related not only to the length of the polypeptide chain being degraded, but also to the content of serine (and possibly threonine). A possible N leads to O acyl shift during the cleavage is a tentative explanation. The programs here represented lead to a significant reduction in background compared to conventional programs and allowed considerable prolongation of the degradations.

Amino Acid Sequence↗
PubMed1973

Applications of a synthetic neuraminidase substrate.

A rapid and precise assay for neuraminidase using 2-(3'-methoxyphenyl)-N-acetyl-alpha-neuraminic acid (MPN) is described. It is proposed that this substrate be used for the standardization of activity of neuraminidases from viral, bacterial, and mammalian sources. MPN is also used as a chromogenic substrate to localize influenza and parainfluenza virus foci in tissue culture. This technique permits the recovery of infective virus from these stained "plaques." It has also been demonstrated that immunoprecipitin lines containing neuraminidase complexes with antibody in the Ouchterlony test can be observed by a similar staining procedure. No enzyme inhibition occurs in the presence of anti-neuraminidase antibodies or concanavalin A when MPN is used as a substrate in contrast to the results with high-molecular-weight substrates such as fetuin.

Animals↗
PubMedDate not supplied

Plasma amino acid concentrations in newborn infants during parenteral nutrition.

Amino acid substance concentrations in plasma have been measured during total and partial parenteral nutrition with Vamin in 12 seriously ill newborn infants. When plasma amino acid concentrations were compared to the levels in reference infants, 11 of 21 were low, among the 11 were seven essential amino acids (Arg, Cys, Ile, Leu, Lys, Thr, Tyr), while concentrations above the reference median and range occurred for seven amino acids. For three (Asp, Glu, Phe) levels were exceptionally high. From these findings, from studies by others on amino acid levels during parenteral nutrition with Vamin, and from amino acid needs judged from venous-arterial differences in newborns, an amino acid preparation for parenteral administration to newborn infants is suggested.

Amino Acids↗
PubMedDate not supplied

Elastosis and cancer.

Recently we have shown that the autofluorescence within or just outside of a malignant tumor is rather small or large resp. in comparison to healthy tissue when excited at 365 nm. Studies with unfixed, unstained cryosections of skin with melanomas have revealed bulky fiber-like structures with a high fluorescence intensity just outside of a malignant tumor. Using polarized light, the structures could be identified as elastic fibers. This was also confirmed by studies on arterial walls.

Aged↗
PubMedDate not supplied

[The antigenic interrelationships between influenza A (H2) viruses determined by the mathematical processing of the data from immunoenzyme analysis using monoclonal antibodies to the M1 and NP proteins].

Antigenic relationships among 15 influenza A (H2) virus strains of human and avian origin were determined by ELISA titers with monoclonal antibodies (MCA) to Ml and NP proteins. Minor antigenic variations were found in Ml protein. One MCA to NP protein (469/6) showed different reactivity with human and avian influenza viruses. Analyses of antigenic relationships among influenza viruses were performed according to a computerized taxonomic cluster procedure. The evolutionary relatedness of these viruses is discussed.

Animals↗
PubMedDate not supplied

[The effect of detergents on the physicochemical and immunochemical properties of the isolated M1 protein of the influenza virus].

The degree of solubility of influenza virus protein M1 preparations isolated from virions by acid chloroform-methanol extraction was studied under the effect of a wide spectrum of detergents of different origin. The same detergents were used for solution of a lipid comprising a part of artificially formed liposomes. Only some of the detergents used (sodium dodecyl sulfate, SDS, triton X-100, and disintegron-B) were shown to be optimal for solution of both influenza virus protein M1 and lipid. The degree of effect on the immunochemical properties of protein ML isolated from influenza virus virion of the above-mentioned detergents optimal for solution was also studied. For this purpose, a panel of 18 monoclonal antibodies with different determinant specificity to protein M1 was used. Two of the three detergents (SDS and disintegron-B) were shown not to change the antigenic profile of protein M1. The immunochemical properties of protein M1 of influenza virus isolated from virions by two methods: chloroform-methanol extraction and preparative polyacryl amide gel electrophoresis, were studied. These two methods of protein M1 isolation were shown not to alter its immunochemical properties.

Antibodies, Monoclonal↗