Obtaining a protein concentrate from integral defatted sunflower flour

Proteins which are found in integral defatted sunflower flour (27% of protein in dry weight) allow us to produce a protein concentrate by means of extraction of proteins with a basic pH solution, followed by their precipitation with an acid pH solution. Once the suitable conditions for pH and temperature were fixed in order to carry out these processes, a solid proteic concentrate (71% of protein in dry weight) was obtained which was rich in glutamic and aspartic acids, with a liquid supernatant very rich in phosphorus and potassium, which might be used as an agricultural fertilizer.     

Amino acid and cDNA sequences of a methionine-rich 2S protein from sunflower seed (Helianthus annuus L.)

The amino acid sequence of a methionine-rich 2S seed protein from sunflower (Helianthus annuus L.) and the sequence of a cDNA clone which codes for the entire primary translation product have been determined. The mature protein consists of a single polypeptide chain of 103 amino acids (molecular mass 12133 Da) which contains 16 residues of methionine and 8 residues of cysteine. The cDNA sequence established that the protein is synthesized as a precursor of 141 residues with a typical hydrophobic signal sequence of 25 residues followed by a further 13-residue hydrophobic pro-sequence which is presumably removed by post-translational cleavage. The sequence of the mature protein and that deduced from the cDNA were identical with no evidence of processing at the C-terminus. Comparison of the sunflower methionine-rich protein sequence with sequences of other seed 2S proteins from dicotyledons and monocotyledons showed limited but distinct sequence similarities; in particular the arrangement of the cysteine residues was conserved. The sunflower protein shows 34% identity with the methionine-rich Brazil nut 2S protein and the prepro regions of the precursors of these two proteins show about 50% identity. This similarity indicates that these methionine-rich 2S proteins have diverged as a subclass of the 2S superfamily of proteins which contain only 2-3% methionine. While the related 2S proteins from other dicotyledons are processed to a small and large subunit, the sunflower protein is not cleaved in this way.     

Characterization of a phosphorus-potassium solution obtained during a protein concentrate process from sunflower flour. Application on rye-grass

The process that permits the ability to obtain a protein extract from defatted sunflower flour also produces a solution very rich in phosphorus (P) and potassium (K), which also contains small concentrations of humic substances. The aim of this study has been to determine the possible agricultural use of this extract. Therefore the phosphorus-potassium solution (experimental solution) was analyzed to determinate its pH and its content of nitrogen, proteins, organic carbon, humic substances potassium and phosphorous. The experimental solution was applied on rye-grass (Lolium multiflorum Lam.) and afterwards the results were analyzed we calculated the germination percentage and the fresh and dry weights that were obtained after each cut throughout the duration of the experiment. In addition the different pigment types (chlorophyll a, chlorophyll b and carotenoids) were quantified. The conclusions of the study examine how this time-stable experimental solution improves the long-term effects and also the level of pigments, especially carotenoids, of the plants that have been treated.     

Amino acid sequence of a calcium-binding protein (TCBP-10) from Tetrahymena

The amino acid sequence of a calcium-binding protein obtained from the cilium and cell body of Tetrahymena, designated as TCBP-10 (Tetrahymena calcium-binding protein; molecular mass = 10 kDa [Ohnishi, K. and Watanabe, Y. (1983) J. Biol. Chem. 258, 13978-13985] was determined. It is composed of 102 amino acid residues. The exact molecular mass is calculated to be 11563 Da. From the amino acid sequence analysis, it has two EF-hand-type calcium-binding sites.     

Amino acid sequence of a peptide from keratan sulfate II-core protein linkage regions

Keratan sulfate II was prepared from the proteolytic digest of pig nucleus pulposus proteoglycan. The polysaccharide chains containing the fragment peptides of the core protein at their reducing terminal were subjected to anhydrous HF-solvolysis reaction and one of the glycopeptides from the keratan sulfate II-core protein linkage regions was isolated. The amino acid sequence of the peptide was deduced to be Ala-Pro-Ser-Pro-Gly, which is different from those reported for the attachment sites of chondroitin sulfate on core proteins from various sources. The results provided the first solid amino acid sequence for the keratan sulfate II-core protein linkage regions and suggested that the amino acid sequence of the core protein might determine the distribution of chondroitin sulfates and keratan sulfates along the core protein of the proteoglycan molecule.     

Amino acid sequence of a sarcoplasmic calcium-binding protein from the sandworm Nereis diversicolor

Muscles of invertebrate species contain abundant quantities of soluble, sarcoplasmic, high affinity Ca2+-binding proteins (SCBPs). The SCBPs belong to the calmodulin superfamily and contain four homologous domains (I-IV) which arose by reduplication of a gene for a small ancestral protein. We have determined the amino acid sequence of the SCBP from the sandworm Nereis diversicolor. This protein is the only SCBP which has been crystallized in a form suitable for three-dimensional structure determination by high-resolution x-ray analysis (Babu, Y. S., Cox, J. A., and Cook, W. J. (1987) J. Biol. Chem. 262, 11184-11185). N. diversicolor SCBP is a single polypeptide chain of 174 amino acids, including single residues of glutamine and histidine, 2 tyrosines, and 3 tryptophans. It is devoid of cysteine and has an acetylated amino terminus, a calculated Mr of 19,485, and a net charge of -13 at neutral pH. There was no evidence for heterogeneity in the sequence. Probable Ca2+-binding sites were recognized in domains I, III, and IV. Comparison with other available invertebrate SCBP sequences shows an unusually high degree of variability among these proteins, with only 9 residues common to all species.     

Amino acid supplementation improves heterologous protein production by Saccharomyces cerevisiae in defined medium

Supplementation of a chemically defined medium with amino acids or succinate to improve heterologous xylanase production by a prototrophic Saccharomyces cerevisiae transformant was investigated. The corresponding xylanase production during growth on ethanol in batch culture and in glucose-limited chemostat culture were quantified, as the native ADH2 promoter regulating xylanase expression was derepressed under these conditions. The addition of a balanced mixture of the preferred amino acids, Ala, Arg, Asn, Glu, Gln and Gly, improved both biomass and xylanase production, whereas several other individual amino acids inhibited biomass and/or xylanase production. Heterologous protein production by the recombinant yeast was also improved by supplementing the medium with succinate. The production of heterologous xylanase during growth on ethanol or glucose could thus be improved by supplementing metabolic precursors in the carbon- or nitrogen-metabolism.     

Amino acid sequence of acyl-CoA-binding protein from cow liver.

Acyl-CoA-binding protein from bovine liver was purified with the use of reverse-phase h.p.l.c. in the final step. The complete amino acid sequence was determined by using a combination of gas-phase Edman degradation and electron-impact and fast-atom-bombardment mass spectrometry. The sequence was confirmed by determination of the Mr by plasma-desorption time-of-flight mass spectrometry.     

Amino acid composition and protein dimension

There is indirect evidence that the amino acid composition of proteins depends on their dimension. The amino acid composition of a nonredundant set of about 550,000 proteins was determined and it was observed that, in the range of 50-200 residues, the percentage of occurrence of most of the residue types significantly depends on protein dimension. This result should prove useful in analyzing protein sequences and genomics.     

Amino acid sequence of nitrite reductase: a copper protein from Achromobacter cycloclastes.

The amino acid sequence of the copper-containing nitrite reductase (EC 1.7.99.3) from Achromobacter cycloclastes strain IAM 1013 has been determined by using peptides derived from digestion with Achromobacter protease I (Lys), Staphylococcus aureus V8 protease (Glu), cyanogen bromide, and BNPS-skatole in acetic acid. The subunit contains 340 amino acids. The identity of the first seven amino acids is tentative. The sequence has been instrumental in the X-ray structure determination of this molecule; in conjunction with the X-ray structure, ligands to a type I copper atom and a type II copper atom (one of each per subunit) have been identified. Comparison of the sequence to those of multi-copper oxidases such as ascorbate oxidase, laccase, and ceruloplasmin [Messerschmidt, A., & Huber, R. (1990) Eur. J. Biochem. 187, 341-352] reveals that each of two domains seen in the X-ray structure is similar to the oxidases and also to the small blue copper-containing proteins such as plastocyanin. The combination of sequence and structural similarity to ascorbate oxidase and sequence similarity to ceruloplasmin leads to a plausible model for the domain structure of ceruloplasmin.     

Amino acid sequence of vitamin D-dependent calcium-binding protein from bovine cerebellum

The amino acid sequence of vitamin D-dependent calcium-binding protein from bovine cerebellum has been determined. It is composed of 260 amino acid residues and its N-terminus is acetylated. The molecular mass is calculated to be 29 851 Da. The presence of six calcium-binding sites (I-VI) has been proposed, two of them (sites II and VI) have lost their calcium-binding function through amino acid replacements, and the other four are able to bind calcium. Six calcium-binding domains are supposed to be derived from two gene duplications of the two ancestral calcium-binding domains. In comparison with the sequence of chick intestinal calcium-binding protein deduced from a cDNA sequence [(1985) Nucleic Acids Res. 13, 8867-8881], the bovine calcium-binding protein is two amino acid residues shorter at the N-terminus and the other parts show 78.5% identity.     

Amino acid sequence of the encephalitogenic basic protein from human myelin

Myelin from the central nervous system contains an unusual basic protein, which can induce experimental autoimmune encephalomyelitis. The basic protein from human brain was digested with trypsin and other enzymes and the sequence of the 170 amino acids was determined. The localization of the encephalitogenic determinants was described. Possible roles for the protein in the structure and function of myelin are discussed.     

解淀粉芽孢杆菌3-2发酵羽毛产氨基酸

【目的】建立废弃羽毛液体发酵工艺,优化发酵条件,提高羽毛降解率及氨基酸产量,研发新型、高效复合氨基酸肥料。【方法】利用解淀粉芽孢杆菌3-2发酵羽毛,探究温度、发酵时间、羽毛含量、单一碳源、复合碳氮源、金属离子等对废弃羽毛降解效果以及发酵液中氨基酸种类和含量的影响。【结果】废弃羽毛降解率与氨基酸总产量呈负相关。随着发酵时间延长,羽毛降解率增加,当发酵温度为37°C、羽毛添加量为1%、以乳糖为外加碳源、添加Mg2+时,羽毛降解率最高,达到81.92%。随着羽毛添加量增加,氨基酸总含量也增加(在20%范围以内),当发酵温度为37°C、降解时间为108 h、羽毛添加量为10%、乳糖添加量为0.5%、不添加复合碳氮源、不添加金属离子时,氨基酸的种类最全(富含17种氨基酸),总含量最高,达到20.861 g/kg。【结论】利用解淀粉芽孢杆菌3-2发酵废弃羽毛生产氨基酸复合肥料是一种可靠、环保、经济的方法,获得的氨基酸肥料营养齐全。研究结果为新型复合氨基酸肥料的研发提供技术支撑。