1. Circular dichroism studies on synthetic signal peptides
G L Reddy, R Nagaraj Biochim Biophys Acta. 1985 Oct 18;831(3):340-6. doi: 10.1016/0167-4838(85)90117-7.
Circular dichroism studies on synthetic peptides corresponding to the signal sequences of chicken lysozyme and Escherichia coli proteins, lambda-receptor and lipoprotein, have been carried out in trifluoroethanol. The peptides, (CH3)3-C-O-CO-Thr-Leu-Lys-Lys-Leu-Pro-Leu-Ala-Val-Ala-Val-Ala-Ala-Gly- Val-Met-Thr-Ala- Ala-Met-Ala-OCH3, (CH3)3-C-O-CO-Met-Lys-Ser-Leu-Leu-Ile-Leu-Val-Leu-Cys(benzyl)- Phe-Leu-Pro- Leu-Ala-Ala-Leu-Gly-OH and (CH3)3-C-O-CO-Leu-Val-Leu-Gly-Ala-Val-Ile-Leu-Gly- Thr-Thr-Leu-Leu- Ala-Gly-OCH3, corresponding to the signal sequences of lambda-receptor, lysozyme and the hydrophobic region of lipoprotein, respectively, show two negative bands at approx. 205 and 220 nm, characteristic of an alpha-helical conformation. Secondary structural features are discernible even in the shorter, 12-residue carboxy-terminal fragments of these signal peptides. A comparison of the conformation of the amino-terminal, central and carboxy-terminal fragments of lipoprotein signal sequence indicates that the central octapeptide fragment is more structurally ordered compared to the amino- and carboxy-terminal fragments.
2. Amino acid sequence of human tumor derived angiogenin
D J Strydom, J W Fett, R R Lobb, E M Alderman, J L Bethune, J F Riordan, B L Vallee Biochemistry. 1985 Sep 24;24(20):5486-94. doi: 10.1021/bi00341a031.
The amino acid sequence and disulfide bond pairing of human tumor derived angiogenin, the first tumor angiogenesis factor to be isolated in pure form from human sources, have been determined by conventional sequencing techniques adapted and applied to nanomole and subnanomole levels of material. Angiogenin, obtained from conditioned media of a human colonic adenocarcinoma cell line, is a single-chain protein consisting of 123 amino acids with the following sequences: less than Glu1-Asp-Asn-Ser-Arg-Tyr-Thr-His- Phe-Leu-Thr-Gln-His-Tyr-Asp15-Ala-Lys-Pro-Gln-Gly-Arg-Asp-Asp- Arg-Tyr-Cys-Glu-Ser-Ile-Met30- Arg-Arg-Arg-Gly-Leu-Thr-Ser-Pro-Cys-Lys-Asp-Ile-Asn-Thr- Phe45-Ile-His-Gly-Asn-Lys-Arg-Ser -Ile-Lys-Ala-Ile-Cys-Glu-Asn-Lys60-Asn-Gly-Asn-Pro-His-Arg-Glu-Asn -Leu-Arg-Ile -Ser-Lys-Ser-Ser75 -Phe-Gln-Val-Thr-Thr-Cys-Lys-Leu-His-Gly-Gly-Ser-Pro-Trp-Pro90-Pro -Cys-Gln-Tyr -Arg-Ala-Thr-Ala -Gly-Phe-Arg-Asn-Val-Val-Val105-Ala-Cys-Glu-Asn-Gly-Leu-Pro-Val- His-Leu-Asp-Gln-Ser-Ile-Phe120-Arg-Arg-Pro123-OH. Three disulfide bonds link the half-cystinyl residues 26-81, 39-92, and 57-107. The sequence is homologous to that of the pancreatic ribonucleases with 35% identity and many of the remaining residues conservatively replaced. Similarities are especially apparent around the major active-site residues His-12, Lys-41, and His-119 of ribonuclease which are conserved as are three of the four disulfide bonds.(ABSTRACT TRUNCATED AT 250 WORDS)
3. Largomycin: preparation, properties, and structure
D D Vandré, A Zaheer, S Squier, R Montgomery Biochemistry. 1982 Sep 28;21(20):5089-96. doi: 10.1021/bi00263a037.
Largomycin has been purified to homogeneity by chromatography on hydroxylapatite whereby carbohydrate and protease impurities were removed. Largomycin is an acidic protein (pI 4.13, molecular weight 29300) which forms a dimer in phosphate buffer. An N-terminal amino acid sequence analysis from the amino-terminal residue gave, for the first 32 residues, Asp-Ile-Leu-Ile-Ala-Gly-Ala-Thr-Gly-Asn-Val-Gly-Lys-Pro-Leu-Val-Glu-Gly-Leu-Leu - Ala-Ala-Gly-Lys-Pro-Val-Arg-Ala-Leu-Thr-Arg-Asn... The sequence from the carboxyl terminus was -Ala-Ala-Leu-Phe-OH with threonine, valine, and glutamic acid being released upon prolonged digestion. The same amino acid sequences were found for largomycin prepared from either the culture broth or the mycelium of Streptomyces pluricolorescens. The similarities extended to the other physical properties, the antimicrobial activity against Staphylococcus aureus and Sarcina lutea, and the antitumor activity against KB cells. Largomycin inhibits the biosynthesis of DNA and RNA. An iodinated derivative did not bind to KB cells. The antimicrobial activity was lost following ultraviolet irradiation, protection against which was not afforded by p-aminobenzoic acid.
