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CHLOROPLAST GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE (NADP): AMINO ACID SEQUENCE OF THE SUBUNITS FROM ISOENZYME I AND STRUCTURAL RELATIONSHIP WITH ISOENZYME II
No full textThe structural relationship between isoenzymes I and II of chloroplast glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate: NADP+ oxidoreductase (phosphorylating) EC 1.2.1.13) has been established at the protein level. The complete primary structure of subunits A and B of glyceraldehyde-3-phosphate dehydrogenase I from Spinacia oleracea has been determined by sequence analysis of the corresponding tryptic peptides, aligned by fragments derived from cyanogen bromide and Staphylococcus proteinase V8 digestions and by partially sequencing each intact subunit. Subunit A has an Mr of 36,225 and consists of 337 amino acid residues, whilst subunit B (Mr 39,355) consists of 368 residues. The amino acid sequence of subunit B, as determined through direct analysis of the protein, is identical to that recently deduced at cDNA level (Brinkmann et al. (1989) Plant Mol. Biol. 13, 81-94). The two subunits share a common portion of amino acid sequence which differs by 66 amino acid residues. Subunit B has an extra C-terminal sequence of 31 amino acid residues. Chloroplast glyceraldehyde-3-phosphate dehydrogenase II was partially characterized by sequencing the N-terminal portion of the intact protein and some of its tryptic peptides. The sequences of all the examined fragments fit precisely that of the corresponding regions of subunit A from glyceraldehyde-3-phosphate dehydrogenase I
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
THE BOVINE PLASMA RETINOL-BINDING PROTEIN. AMINO ACID SEQUENCE, INTERACTION WITH TRANSTHYRETIN, CRYSTALLIZATION AND PRELIMINARY X-RAY DATA
No full text1. The primary structure of bovine plasma retinol-binding protein (RBP) has been determined and found to be more than 90% identical to human and rabbit RBPs, and more than 80% identical to rat RBP. Main changes in amino acid sequence are observed in two regions on the surface of the protein molecule (residues 138-148 and 169-183). 2. The interactions of bovine RBP with bovine and human transthyretins were investigated using the technique of fluorescence polarization. Bovine RBP was able to form high affinity complexes (K'd = 0.34 +/- 0.02 microM) with both bovine and human transthyretins, displaying a stoichiometry of approximately 2 molecules RBP/molecule transthyretin in both cases. The sites that participate in protein-protein interactions are thus very similar, and this tends to exclude the involvement of the superficial regions more significantly substituted in mammalian RBPs (residues 138-151 and 167-183) in the protein-protein recognition. 3. Bovine RBP has been crystallized (space group P2(1)2(1)2(1), with a = 4.61 nm, b = 4.91 nm, c = 7.61 nm) and the crystals are suitable for high-resolution X-ray diffraction studies
Separation of fragments from human serum albumin and its charged variants by reversed-phase and cation-exchange high-performance liquid chromatography.
No full textReversed-phase high-performance liquid chromatography (RP-HPLC) and ion-exchange chromatography on poly(2-sulphoethylaspartamide)-silica (SCX) were compared as alternative approaches in characterizing charged genetic variants of human serum albumin. The chromatographic behaviour of cyanogen bromide (CNBr), tryptic and V8 protease digests from normal and mutant albumins were examined. The results showed that substituted site-containing CNBr fragments are successfully resolved by RP-HPLC; in most instances SCX and RP-HPLC are equally adequate in identifying the modified tryptic peptides from CNBr fragments; although generally useful, SCX chromatography is specifically needed in all instances where amino acid replacement is occurring in a small hydrophilic tryptic fragment and choosing Staphylococcus aureus V8 protease instead of tryptic digestion is advantageous
Bovine Plasma Retinol-Binding Protein: Amino Acid Sequence, Interaction with Transthyretin, Crystallization and Preliminary X-Ray Data
No full textThe molecular defect in a COOH-terminal-modified and shortened mutant of human serum albumin.
No full textAlbumin Venezia is a fast migrating genetic variant of human serum albumin which, in heterozygous subjects, represents about 30% of the circulating protein. The molecular defect in this variant was studied in a subject possessing an atypical level of the mutant (80% of the total protein) and in other members of his family. Albumins, isolated from the sera of the propositus and his heterozygous relatives, were treated with CNBr and the resulting fragments analyzed by isoelectric focusing. The peptides were then isolated in a homogeneous form by reverse-phase high performance liquid chromatography and submitted to sequence analysis. The results show that albumin Venezia possesses a shortened polypeptide chain, 578 residues instead of 585, completely variant from residue 572 to the COOH-terminal end: sequence: (see text). This extensive modification may be accounted for by the deletion of exon 14 and translation to the first terminator codon of exon 15, which normally does not code for protein. The absence of a basic COOH-terminal dipeptide in the mature molecule can be explained by the probable action of serum carboxypeptidase N. Additional support for such action comes from examination of the remaining 20% of the total albumin of the propositus, which is found to contain an extra Arg at its COOH terminus, probably due to partial digestion by carboxypeptidase N. The low serum level of the variant in heterozygous subjects suggests that the COOH-terminal end of the molecule is critical for albumin stability
The role of comorbidities in duration of untreated illness for bipolar spectrum disorders
No full textBackground Growing interest has been given to the construct of Duration of untreated illness (DUI) on the outcome of bipolar disorder (BD), due to its potentially modifiable nature. The aim of this study was to identify possible clinical correlates of DUI in a sample of BD patients. Method 119 BD spectrum patients included. DUI rate was calculated and dichotomized into short DUI and long DUI subgroups, cut-off 24 months. These subgroups were compared for socio-demographic and clinical variables. Significant results were included into direct logistic regressions to assess their impact on the likelihood of presenting with long DUI. Results Mean DUI±SD was 75.6±98.3 months. Short DUI subgroup comprised 56 (47.1%), long DUI 60 (52.9%) patients. Age at onset of BD was lower in the long DUI subgroup (p=0.021), illness duration longer (p=0.011). Long DUI subgroup showed significantly more comorbidity with Axis I (p=0.002) and personality disorders (p=0.017), less interepisodic recovery (p<0.001) and less Manic Predominant Polarity (p=0.009). Direct logistic regression as a full model was significant, correctly classifying 76.7% of cases. A unique statistically significant contribution was made by: Manic Predominant Polarity, Personality Disorder Comorbidity, and Total Changes in Medications. Limitations Partial retrospective data, cross sectional study. Conclusions DUI was longer than 24 months in half of the sample. Psychotic /Manic onset contributed to a quick diagnostic classification. Personality disorders in depressed patients could delay a correct diagnosis of BD, factors associated with an increased likelihood of BD must be considered. More research on personality disorder comorbidities is needed
High-performance liquid chromatography of complex mixtures of cyanogen bromide-produced peptides from different proteins.
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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