The histopathology and ultrastructure of steatitis affecting common dab Limanda limanda.

This study presents a new description, based on histopathological and ultrastructural studies, of a disease affecting the common dab Limanda limanda (L.). The condition can be recognised by the presence of multiple orange or yellow lesions in the pterygophorial region of the fish. The principal histopathological features are necrosis of fat cells, extensive macrophage infiltration leading to the formation of granulomatous structures, and the accumulation of lipopigment by lipid peroxidation. Based on this description, the condition has been diagnosed as steatitis. Although pathology associated with lipid peroxidation is the dominant characteristic of the lesions examined, it is proposed that this process is secondary to necrosis of the adipose tissue. The aetiology is discussed in the light of these observations. In addition, the first record of this condition affecting long rough dab Hippoglossoides platessoides (Fabricius) is made.

The interaction site for tamoxifen aziridine with the bovine estrogen receptor.

Calf uterine estrogen receptor was covalently labeled with [3H]tamoxifen aziridine during affinity chromatography purification. After carboxymethylation, affinity labeled receptor was digested with trypsin under limit conditions and the labeled peptides were fractionated by reversed-phase high performance liquid chromatography into one major and two minor components. Sequence analysis of the dominant labeled fragment indicated the facile cleavage of label during Edman degradation but identified two peptides, both derived from the extreme carboxyl terminus of the steroid-binding domain. The 17 residues of one peptide were fully conserved in all estrogen receptors. This fragment contained five nucleophilic amino acids and was considered as the more favored interaction site for tamoxifen aziridine. A corresponding region of the glucocorticoid receptor has recently been identified as one of three major contact sites for glucocorticoids (Carlstedt-Duke, J., Strömstedt, P.-E., Persson, B., Cederlund, E., Gustafsson, J.-A., and Jörnvall, H. (1988) J. Biol. Chem. 263, 6842-6846). A comparison of amino acid physical characteristics in the hormone-binding domains of human estrogen and glucocorticoid receptors demonstrated an excellent structural correlation between the two regions and delineated elements in the estrogen receptor which may be directly involved in estradiol binding.

Purification of quadrol for microsequencing in the spinning-cup sequenator.

Treatment of Quadrol buffer with isothiocyanatophenylthiocarbamylaminoethylaminopropyl glass (DITC glass) substantially reduces the impurities observed when this buffer is used with the spinning cup sequenator. Use of DITC glass-treated Quadrol buffer permits identification of PTH-amino acids from protein degradations down to 100 pmol.

Amino acid sequence of a basic blue protein from cucumber seedlings.

The amino acid sequence of a type 1 copper protein, the 96-residue basic blue protein from cucumber seedlings, has been determined by Edman degradation of the intact molecule and of fragments produced by cleavage with cyanogen bromide and with trypsin. The cucumber basic blue protein shows a marked sequence homology with stellacyanin, and to a smaller degree with plastocyanin and azurin. The known copper ligands of plastocyanin and azurin (corresponding to histidine-37, cysteine-84, histidine-87, and methionine-92 in plastocyanin) are present in the cucumber basic blue protein. However, the latter also contains a half-cystine residue analogous to the suggested fourth ligand of stellacyanin, where methionine is absent.

Complete covalent structure of human platelet factor 4.

The amino acid sequence of the subunit of human platelet factor 4 has been determined. Human platelet factor 4 consists of identical subunits containing 70 amino acids, each with a molecular weight of 7,756. The molecule contains no methionine, phenylalanine or tryptophan. The proposed amino acid sequence of PF4 is: Glu-Ala-Glu-Glu-Asp-Gly-Asp-Leu-Gln-Cys-Leu-Cys-Val-Lys-Thr-Thr-Ser-Gln-Val-Arg-Pro-Arg-His-Ile-Thr-Ser-Leu-Glu-Val-Ile-Lys-Ala-Gly-Pro-His-Cys-Pro-Thr-Ala-Gln-Leu-Ile-Ala-Thr-Leu-Lys-Asn-Gly-Arg-Lys-Ile-Cys-Leu-Asp-Leu-Gln-Ala-Pro-Leu-Tyr-Lys-Lys-Ile-Ile-Lys-Lys-Leu-Leu-Glu-Ser. From consideration of the homology with beta-thromboglobulin, disulphide bonds between residues 10 and 36 and between residues 12 and 52 can be inferred.

Structural and antigenic studies of an idiotype-bearing murine antibody to the arsonate hapten.

Mice of strain A/J responded to repeated intraperitoneal injection of Limulus hemocyanin derivatized with arsanilic acid by producing large quantities (approximately 5 mg/mL of ascites fluid) of IgG antibodies specific for this hapten. The antibodies possessed a characteristic idiotypic determinant and exhibited restricted heterogeneity as demonstrated by isoelectric focusing and primary N-terminal amino acid sequence analysis of isolated light and heavy polypeptide chains. Both light- and heavy-chain sequences were comparable to those of myeloma proteins in lack of heterogeneity. The N terminus of the light chain exhibited V KI sequence and only one position in the first 30 residues showed more than one amino acid. No variability was observed in the first 10 N-terminal residues of the heavy chain. Rabbit antiserum to the idiotype blocked binding of hapten by the purified antibody. The presence of both light- and heavy-chain antigenic determinants was required for optimal formation of the idiotypic determinant.

Complete covalent structure of human beta-thromboglobulin.

The complete primary structure of the platelet-specific protein human beta-thromboglobulin has been determined. beta-Thromboglobulin consists of identical subunits of 81 amino acids, each with a molecular weight of 8851. The amino acid sequence of the beta-thromboglobulin subunit is: Gly-Lys-Glu-Glu-Ser-Leu-Asp-Ser-Asp-Leu-Tyr-Ala-Glu-Leu-Arg-Cys-Met-Cys-Ile-Lys-Thr-Thr-Ser-Gly-Ile-His-Pro-Lys-Asn-Ile-Gln-Ser-Leu-Glu-Val-Ile-Gly-Lys-Gly-Thr-His-Cys-Asn-Gln-Val-Glu-Val-Ile-Ala-Thr-Leu-Lys-Asp-Gly-Arg-Lys-Ile-Cys-Leu-Asp-Pro-Asp-Ala-Pro-Arg-Ile-Lys-Lys-Ile-Val-Gln-Lys-Lys-Leu-Ala-Gly-Asp-Glu-Ser-Ala-Asp. Disulfide bridge-18 to half-cystine-58. The amino acid sequence of beta-thromboglobulin shows a marked homology with that of platelet factor 4. When the sequences are aligned for maximum homology, 42 of the 81 residues of beta-thromboglobulin are identical with those of platelet factor 4, including the position of the four half-cystines.

Studies on the chemistry of human platelet factor 4.

The chemical characteristics of several PF4 preparations have been examined by gel electrophoresis, amino acid analysis and NH2-terminal amino acid sequence determination. Preparations of PF4 from gel filtration and from affinity chromatography appeared identical. A single NH2-terminal sequence was determined as follows: NH2-Glu-Ala-Glu-Glu-Asp-Gly-Asp-Leu-Gin-SCMCys-Leu-SCMCys-Val-Lys-Thr-Thr-Ser-Gln-Val-Arg-. The molecular weight of the PF4 subunits, which seem to be identical, was 7,100 based on the recovery of NH2-terminal glutamic acid.