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The aim of the study was to determine the effect of whole milk powder (WMP) as heterologous proteins on chicken breast emulsion-type sausages. The quality properties of WMP on such chicken breast emulsion-type sausages were investigated by measuring the proximate composition, pH, color, cooking yield, protein solubility, and by applying other methods, such as texture profile analysis (TPA), microphotograph, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and electronic nose. The crude fat, protein, and ash contents of 15% WMP samples were significantly higher than the control samples (p < 0.05). The redness of the cooked samples significantly increased with an increase in the WMP contents (p < 0.05). The cooking yield of WMP treated samples was significantly higher than the control sample (p < 0.05). Additionally, the hardness, gumminess, and chewiness of WMP treated samples were significantly higher than the control sample (p < 0.05). The sarcoplasmic and myofibrillar proteins of samples containing 15% WMP were significantly higher than the control samples (p < 0.05). The result of SDS-PAGE showed that the C protein, sarcoplasmic protein, actin, and tropomyosin increased with an increase in the WMP contents. The principal component analysis plot of WMP-treated samples was clearly different from that of the control samples. Based on these results, it was predicted that WMP could be useful as heterologous protein on emulsion-type sausage.

Respirovirus C protein blocks the type I interferon (IFN)-stimulated activation of the JAK-STAT pathway. It has been reported that C protein inhibits IFN-α-stimulated tyrosine phosphorylation of STATs, but the underlying mechanism is poorly understood. Here, we show that the C protein of Sendai virus (SeV), a member of the Respirovirus genus, binds to the IFN receptor subunit IFN-α/β receptor subunit (IFNAR)2 and inhibits IFN-α-stimulated tyrosine phosphorylation of the upstream receptor-associated kinases, JAK1 and TYK2. Analysis of various SeV C mutant (Cm) proteins demonstrates the importance of the inhibitory effect on receptor-associated kinase phosphorylation for blockade of JAK-STAT signaling. Furthermore, this inhibitory effect and the IFNAR2 binding capacity are observed for all the respirovirus C proteins examined. Our results suggest that respirovirus C protein inhibits activation of the receptor-associated kinases JAK1 and TYK2 possibly through interaction with IFNAR2.

Antibiotic resistance is a public health threat, and the rise of multidrug-resistant bacteria, including those that form protective biofilms, further compounds this challenge. Antimicrobial peptides (AMPs) have been recognized for their anti-infective properties, including their ability to target processes important for biofilm formation. However, given the vast array of natural and synthetic AMPs, determining potential candidates for anti-biofilm testing is a significant challenge. In this study, we present an in silico approach, based on open-source tools, to identify AMPs with potential anti-biofilm activity. This approach is developed using the sortase-pilin machinery, important for adhesion and biofilm formation, of the multidrug-resistant, biofilm-forming pathogen C. striatum as the target. Using homology modeling, we modeled the structure of the C. striatum sortase C protein, resembling the semi-open lid conformation adopted during pilus biogenesis. Next, we developed a structural library of 5544 natural and synthetic AMPs from sequences in the DRAMP database. From this library, AMPs with known anti-Gram positive activity were filtered, and 100 select AMPs were evaluated for their ability to interact with the sortase C protein using in-silico molecular docking. Based on interacting residues and docking scores, we built a preference scale to categorize candidate AMPs in order of priority for future in vitro and in vivo biofilm studies. The considerations and challenges of our approach, and the resources developed, which includes a search-enabled repository of predicted AMP structures and protein-peptide interaction models relevant to biofilm studies (B-AMP), can be leveraged for similar investigations across other biofilm targets and biofilm-forming pathogens.

Numerous dark-brown-coloured small spots called “Wischnewski spots” are often observed in the gastric mucosa in the patients dying of hypothermia, but the molecular mechanisms through which they develop remain unclear. We hypothesised that hypothermia may activate the secretion of gastric acid and pepsin, leading to the development of the spots. To investigate this, we performed experiments using organotypic rat gastric tissue slices cultured at 37 °C (control) or 32 °C (cold). Cold loading for 6 h lowered the extracellular pH in the culture medium. The mRNA expression of gastrin, which regulates gastric acid secretion, increased after cold loading for 3 h. Cold loading increased the expression of gastric H+,K+-ATPase pump protein in the apical canalicular membrane and resulted in dynamic morphological changes in parietal cells. Cold loading resulted in an increased abundance of pepsin C protein and an elevated mRNA expression of its precursor progastricsin. Collectively, our findings clarified that cold stress induces acidification by activating gastric H+,K+-ATPase pumps and promoting pepsin C release through inducing progastricsin expression on the gastric mucosa, leading to tiny haemorrhages or erosions of the gastric mucosa that manifest as Wischnewski spots in fatal hypothermia.

Background Capsid (C) protein plays an important role in the replication of classical swine fever virus (CSFV). The ubiquitin proteasome system (UPS) involves in replication of many viruses via modulation of viral proteins. The relationship of CSFV with UPS is poorly understood and the impact of 26S proteasome on C protein has never been reported before. Methods In this study, fused C protein with an EGFP tag is expressed in PK-15 and 3D4/2 cells. MG132 and 3-methyladenine (3-MA) are used to detect the roles of 26S proteasome and autophagolysosome in expression levels of C protein. Truncated and mutant C proteins are used to find the exact residues responsible for the degradation of C protein. Immunoprecipitaion is performed to find whether C protein is ubiquitinated or not. Results C-EGFP protein expresses in a cleaved form at a low level and is degraded by 26S proteasome which could be partly inhibited by MG132. C-terminal residues play more important roles in the degradation of C protein than N-terminal residues. Residues 260 to 267, especially M260 and L261, are crucial for the degradation. In addition, C-terminal residues 262 to 267 determine cleavage efficiency of C protein. Conclusions CSFV C protein is degraded by 26S proteasome in a ubiquitin-independent manner. Last 8 residues at C-terminus of immature C protein play a major role in proteasomal degradation of CSFV C protein and determine the cleavage efficiency of C protein by signal peptide peptidase (SPP). Our findings provide valuable help for fully understanding degradation process of C protein and contribute to fully understanding the role of C protein in CSFV replication.

The 11 kDa, positively charged dengue capsid protein (C protein) exists stably as a homodimer and colocalizes with the viral genome within mature viral particles. Its core is composed of four alpha helices encompassing a small hydrophobic patch that may interact with lipids, but approximately 20% of the protein at the N-terminus is intrinsically disordered, making it challenging to elucidate its conformational landscape. Here, we combine small-angle X-ray scattering (SAXS), amide hydrogen-deuterium exchange mass spectrometry (HDXMS), and atomic-resolution molecular dynamics (MD) simulations to probe the dynamics of dengue C proteins. We show that the use of MD force fields (FFs) optimized for intrinsically disordered proteins (IDPs) is necessary to capture their conformational landscape and validate the computationally generated ensembles with reference to SAXS and HDXMS data. Representative ensembles of the C protein dimer are characterized by alternating, clamp-like exposure and occlusion of the internal hydrophobic patch, as well as by residual helical structure at the disordered N-terminus previously identified as a potential source of autoinhibition. Such dynamics are likely to determine the multifunctionality of the C protein during the flavivirus life cycle and hence impact the design of novel antiviral compounds.

Knowledge of the fatigue process in karate sport is essential to improve the performance of top athletes. The physiological and biomechanical behavior during the Karate Specific Aerobic Test (KSAT) fatigue protocol in karate was investigated. PCR, lactate, glucose and cortisol were collected before and after the fatigue protocol application in karate, besides that, and heart rate and technical speed were measured. The results indicated increase in C protein reactive (60%), creatine kinase (25%), cortisol (30%), lactate dehydrogenase (90.9%) and decrease in glucose (21.2%). The maximum speed was: in kizami zuki, 5.75 ± 0.31 m/s; in mawashi geri, 9.0 ± 0.24 m/s, in gyako zuki, 7.23 ± 0.54 m/s and in kizami mawashi geri, 6 ± 0.34 m/s. The mean time for each set was 2.99 ± 0.17 s. There was reduction in speed and duration of set for all techniques, especially in the final sets (p

Neurodegenerative diseases are one of the malfunctions of human nervous system, being a class of complex and prominent pathologies. The human prion Protease Resistant Protein (PrP) is protein regulating copper metabolism in mammalian cells through binding of Cu(II) ions to specific fragments. Nowadays misfolding of this protein is associated with development of prion diseases. Therefore, it is crucial to obtain structural information about coordination of Cu(II) by PrP protein. Herein, we report X-ray absorption spectroscopy (XAS) measurements, carried out on SuperXAS beamline (SLS, PSI Villigen) on PrPC-Cu(II) complexes. Obtained results were compared with theoretical predictions done by FEFF 9.6 software. Complementary to XAS data, Atomic Force Microscopy (AFM) measurements were conducted to obtain low resolution structural information about prepared sample that allow to develop protocol of fixing PrPC molecules on solid substrate used for further experiments. It has been established that folded C-terminal domain of PrPC protein has around 5 nm in diameter. Presented results showed that both XAS and AFM methods are useful tools in detailed examination of complexes of human PrPC either with Cu(II) or with other divalent metal ions.

Background: Ixora coccinea is a tropical ornamental shrub employed in ethnomedicine for the treatment of a number of diseases none of which include the Human Immunodeficiency Virus (HIV) infection. Ixoratannin A-2, one of the constituents, was previously identified via virtual-screening and experimentally confirmed to possess significant anti-HIV-1 activity in an in vitro CD4+ replication assay. This activity was observed to be significantly reduced in degree in viruses lacking the protein Vpu. This suggests the involvement of Vpu as well as other extra-Vpu macromolecules in its antiviral activity. Methods: In the present computational search for the identity of the other macromolecules that could possibly explain the observed activity, a panel of fourteen established HIV-1 macromolecular targets was assembled against which ixoratannin A-2 and other major phytoconstituents of I. coccinea were virtually screened. Results: Structural analyses of the computed ligand-bound complexes, as well as the careful investigation of the thermodynamic attributes of the predicted binding, revealed subtle selectivity patterns at the atomistic level that suggest the likely involvement of multiple macromolecular processes. Some of the binding interactions were found to be thermodynamically favourable, including the multidrug-resistant HIV protease enzyme, CXCR4 and the human elongin C protein all of which formed reasonably strong interactions with ixoratannin A-2 and other constituents of I. coccinea. Conclusion: Ixoratannin A-2’s ability to favourably interact with multiple HIV-1 and human targets could explain its observed extra-Vpu antiviral activity. This, however, does not imply uncontrolled binding with all available targets; on the other hand, molecular size of ixoratannin A-2 and combination of functional groups confer on it a decent level of selectivity against many of the investigated HIV/AIDS targets.

Aptamers are biomaterials that bind to a target molecule through a unique structure, and have high applicability in the diagnostic and medical fields. To effectively utilize aptamers, it is important to analyze the structure of the aptamer binding to the target molecule, however, there are difficulties in experimentally identifying this structure. In the modern pharmaceutical industry, computer-driven docking simulations that predict intermolecular binding models are used to select candidates that effectively bind target molecules. Botulinum toxin (BoNT) is the most poisonous neurotoxin produced from the Clostridium botulinum bacteria, and BoNT/C, one of the eight serotypes, causes paralysis in livestock. In this study, the aptamers that bound to BoNT/C were screened via the systematic evolution of ligands by exponential enrichment, and the binding affinity analysis and binding model were evaluated to select optimal aptamers. Based on surface plasmon resonance analysis and molecular operating environment docking simulation, a pair of aptamers that had high binding affinity to BoNT/C and were bound to different BoNT/C sites were selected. A sandwich assay based on this aptamer pair detected the BoNT/C protein to a concentration as low as ~0.2 ng Ml&minus, 1. These results show that docking simulations are a useful strategy for screening aptamers that bind to specific targets.

Typhoid fever is an endemic disease in Indonesia. Prevention of typhoid fever can be done by administering vaccines. It is known that one of the raw materials for vaccines is a recombinant protein. This study aims to obtain information on the optimum conditions for purification of Salmonella typhi Fim-C recombinant protein with Ni-NTA resin as vaccine raw material. The three main stages of the purification process in this study were binding, washing, and elution of S. typhi Fim-C recombinant proteins. The binding and washing variations of recombinant proteins were carried out twice, four times and six times, while the elution process was carried out at imidazole concentrations of 200 mM, 250 mM, and 300 mM. Purification with a binding process four and six times gave almost the same intensity of S. typhi Fim-C protein bands. Whereas protein was elution at an imidazole concentration of 300 mM showed higher band instability. The results of characterization using SDS-PAGE and analysis using software ImageJ gel analysis showed that the longer the incubation time and the repetition of the binding process, the more protein bound to the resin. Furthermore, the more washing processes are obtained the purer proteins. Based on the data obtained it can be concluded that the purification of the S. typhi Fim-C recombinant protein was optimum at a four-time binding process, six times washing and a 300 mM imidazole concentration. These results are expected to be the basis for recombinant protein refining on a pilot scale and industry scale in better vaccine preparation.

Standard genetic approaches allow the production of protein composites by fusion of polypeptides in head-to-tail fashion. Some applications would benefit from constructions that are genetically impossible, such as the site-specific linkage of proteins via their N or C termini, when a remaining free terminus is required for biological activity. We developed a method for the production of N-to-N and C-to-C dimers, with full retention of the biological activity of both fusion partners and without inflicting chemical damage on the proteins to be joined. We use sortase A to install on the N or C terminus of proteins of interest the requisite modifications to execute a strain-promoted copper-free cycloaddition and show that the ensuing ligation proceeds efficiently. Applied here to protein–protein fusions, the method reported can be extended to connecting proteins with any entity of interest.

e14537Background: Interspecies allometric scaling is used to extrapolate pharmacokinetics (PK) from preclinical data to human PK and dosing. Efficacy of BXQ-350, a novel Saposin C phosphatidylserin...

Envelope viruses maturate by macromolecule assembly and budding. To investigate these steps, we generated virus-like particles (VLPs) by co-expression of structural proteins of Sendai virus (SeV), a prototype of the family Paramyxoviridae. Simultaneous expression of matrix (M), nucleo- (N), fusion (F), and hemagglutinin-neuraminidase (HN) proteins resulted in the generation of VLPs that had morphology and density similar to those of authentic virus particles, although the efficiency of release from cells was significantly lower than that of the virus. By using this VLP formation as a model of virus budding, roles of individual proteins in budding were investigated. The M protein was a driving force of budding, and the F protein facilitated and the HN protein suppressed VLP release. Either of the glycoproteins, F or HN, as well as the N protein, significantly shifted density of VLPs to that of virus particles, suggesting that viral proteins bring about integrity of VLPs by protein–protein interactions. We further found that co-expression of a nonstructural protein, C, but not V, enhanced VLP release to a level comparable to that of virus particles, demonstrating that the C protein plays a role in virus budding.

Sendai virus C protein associates with the signal transducer and activator of transcription (STAT) 1 and inhibits the interferon (IFN) response. We report a molecular basis for the anti-IFN-gamma mechanism of Sendai virus. The C-terminal half-fragment of the C protein (D1) retains both the STAT1-binding and the anti-IFN-gamma abilities comparable to those of the full-size C. IFN-gamma stimulation generates phosphorylated-STAT1 even in the presence of the C or the D1. The phosphorylated-STAT1 generated in the D1-expressing cells forms an aberrant complex, which does not bind to a gamma-activated sequence (GAS) probe. Purified D1, indeed, inhibits in vitro the binding of the phosphorylated-STAT1 dimer to the GAS probe. The D1, however, binds to the STAT1 N-terminal domain, but not the DNA binding domain. These results suggest the possibility that the C protein prevents the gamma-activated factor from binding to GAS elements through its interaction with the STAT1 N-terminal domain.

Conversion of dihydroxyacteone (DHA) to methylglyoxal (MGO) has been shown to be the key mechanism for the growth in "apparent" C-4 sugar content in nonperoxide activity (NPA) manuka honey. This reaction is enhanced by heating and storage time and is demonstrated for the first time in clover honey adulterated with DHA purchased from a chemical supplier and in manuka honey containing naturally occurring DHA and MGO. After heating at 37 °C for 83 days, pure clover honey with no added DHA has the same apparent C-4 sugar content as at t = 0 days. The same clover honey adulterated with synthetic DHA added at t = 0 days and heated at 37 °C over the same time scale shows a change in apparent C-4 sugars from 2.8 to 5.0%. Four NPA manuka honeys heated over longer periods show an increase in apparent C-4 sugars of up to 280% after 241 days. This study strongly suggests that a protein fractionation effect occurs in the conversion of DHA to MGO in higher NPA manuka honey, rendering the remaining δ(13)C protein value more negative and falsely indicating C-4 sugar addition when using the AOAC 998.12 method.

Gradient gel electrophoresis was used to examine the separation properties of novel cross-linking compounds for polyacrylamide (PAAm). At low %T and at the same %C protein migration difference is accentuated for bismethacrylamide cross-linked networks relative to bisacrylamide cross-linked networks. Similar properties were observed for cyclic monomers at low %T. This trend is maintained throughout the gradient. However, at higher %T migration differential relative to N,N'-methylenebisacrylamide (Bis) was less pronounced. Evidence from gradient gels suggests that reactivity and functionality of vinyl groups impose an overriding control over network formation.

To investigate the role of adhesion molecules in C protein-induced myositis (CIM), a murine model of polymyositis (PM).CIM was induced in wild-type mice, L-selectin-deficient (L-selectin(-/-) ) mice, intercellular adhesion molecule 1 (ICAM-1)-deficient (ICAM-1(-/-) ) mice, and mice deficient in both L-selectin and ICAM-1 (L-selectin(-/-) ICAM-1(-/-) mice). Myositis severity, inflammatory cell infiltration, and messenger RNA expression in the inflamed muscles were analyzed. The effect of dendritic polyglycerol sulfate, a synthetic inhibitor that suppresses the function of L-selectin and endothelial P-selectin, was also examined.L-selectin(-/-) mice and L-selectin(-/-) ICAM-1(-/-) mice developed significantly less severe myositis compared to wild-type mice, while ICAM-1 deficiency did not inhibit the development of myositis. L-selectin(-/-) mice that received wild-type T cells developed myositis. Treatment with dendritic polyglycerol sulfate significantly diminished the severity of myositis in wild-type mice compared to treatment with control.These data indicate that L-selectin plays a major role in the development of CIM, whereas ICAM-1 plays a lesser role, if any, in the development of CIM. L-selectin-targeted therapy may be a candidate for the treatment of PM.

The binding of IgA with C-protein was studied and compared with that of jacalin. SDS- PAGE and Western blotting for various human IgA forms (IgA1, IgA2, serum IgA and secretory IgA) proved the specificity of C-protein binding and the superiority of biotinylated C-protein over biotinylated jacalin as probing immunochemical reagent for IgA detection. The obtained results proved the usefulness of employing C-protein / sepharose columns in isolation of IgA from the whole serum. Although, a linear quantitative relationship was established with pure IgA, the development of ELISA technique for quantification of IgA in whole serum was not possible in the present study. However, a proposed procedure was set for further work.

Los autores describen los fundamentos y la utilidad clínica de algunas pruebas de laboratorio: velocidad de sedimentación globular o eritrosedimentación, Dímero D, investigación de trombofilia, proteína C reactiva (PCR) y hemograma.

Extraction of regulatory proteins from thick and thin filaments of vertebrate striated muscle has proven to be an important approach in elucidating roles of these proteins in regulating contraction and in probing specific mechanisms of activation. For some proteins, such as LC2 and C protein, extraction has been fundamental in demonstrating the importance of these proteins in modulating contraction and the kinetics of cross-bridge interaction. For other proteins, such as TnC and troponin, extraction has provided significant insight into the importance of thin-filament intermolecular cooperativity in modulating Ca2+ sensitivity of the contractile process. A combination of extraction and readdition has provided a means of introducing mutated or derivatized proteins into fibers to accomplish a variety of experimental objectives. The use of this approach is likely to grow with the need to test the functional consequences of site-specific mutations as part of studies directed to mechanisms of regulation or altered regulation in heart and skeletal muscles under normal and pathophysiological conditions. Such studies are likely to include extraction in combination with other probes of function such as flash photolysis of reaction substrates or products within the cross-bridge interaction cycle. Although extraction is a powerful approach and is likely to be extended to proteins not discussed in this review, an essential element of experimental design in studies such as these is that appropriate control experiments be done to verify that observed effects of the extraction protocol are specifically attributable to the protein that is removed.

Foram caracterizadas e identificadas as frações proteicas constituintes do capim-mombaça submetido a quatro doses de nitrogênio (0, 100, 300 e 500kg.ha-1) em duas alturas de corte no período chuvoso e no seco. Utilizou-se delineamento experimental em blocos casualizados, em esquema fatorial 4 x 2, com quatro repetições. Os teores de proteína bruta (PB) e das frações A, B1, B2, B3 e C da proteína do capim-mombaça, cortado a 0,20 e 0,40m da superfície do solo foram avaliados pelo Cornell Net Carbohydrate and Protein System. Em relação ao teor de PB, ocorreu diferença significativa (P

Avaliaram-se a composição bromatológica, as frações da proteína bruta (A, B1, B2, B3 e C) e dos carboidratos totais (A, B1, B2 e C) e as respectivas taxas de digestão das frações B1, B2 e B3 de proteínas e das frações A + B1 e B2 de carboidratos e do feno de capim-tifton 85, obtido de plantas colhidas com 28, 35, 42 e 56 dias de rebrota, adubadas com 75 kg/ha/corte de N. Os teores protéicos dos fenos com idades de rebrota de 28 a 56 dias variaram de 17,58 a 12,58%. Os valores das frações protéicas A, B1, B2, B3 e C apresentaram-se, respectivamente, entre 22,10 e 35,53%; 0,24 e 4,55%; 30,37 e 31,34%; 26,55 e 36,62%; e 5,75 e 6,76%, como proporções da proteína bruta total, nos fenos com idades de rebrota entre 28 e 56 dias. As taxas de digestão das frações protéicas B1, B2 e B3 encontraram-se entre 0,319 e 1,324; 0,0724 e 0,0936; e 0,0077 e 0,012 h -1, respectivamente, nos fenos com idades de rebrota entre 28 e 56 dias. Os teores de carboidratos totais variaram de 72,98 a 78,77%, em fenos com 28 a 56 dias de rebrota. Os valores das frações A, B1, B2 e C de carboidratos apresentaram-se entre 2,73 e 5,44%; 1,91 e 2,35%; 77,49 e 80,59%; e 13,59 e 17,87%, respectivamente, como proporções dos carboidratos totais, em fenos com idades entre 28 e 56 dias de rebrota. As taxas de digestão das frações de carboidratos A + B1 e B2 encontraram-se entre 0,181 e 0,20 e 0,04 e 0,0466 h -1, respectivamente, em fenos com idades entre 28 e 56 dias de rebrota. The chemical composition, crude protein fractions (A, B1, B2, B3 and C) and total carbohydrate fractions (A, B1, B2 and C), and respective degradation rate of B1, B2 and B3 protein fractions and A + B1 and B2 carbohydrate fractions of Tifton 85 bermudagrass hay from plants harvested with 28, 35, 42 and 56 days of regrowth, fertilized with 75 kg/ha/cut of N, were evaluated. The protein content of hays from 28 to 56 days of regrowth ranged from 17.58 to 12.58%. The values of A, B1, B2, B3 and C protein fractions presented between 22.1 and 35.53%; 0.24 and 4.55%; 30.37 and 31.34%; 26.55 and 36.62%, and, 5.75 and 6.76%, respectively, as a percentage of the total crude protein, in the hays with ages between 28 and 56 days of regrowth. The degradation rate of B1, B2 and B3 protein fractions presented between 0.319 and 1.324; 0.0724 and 0.0936, and, 0.0077 and 0.012 h -1, respectively, in the hays with ages between 28 and 56 days of regrowth. The total carbohydrates content ranged from 72.98 to 78.77%, for the hays with 28 to 56 days of age. The values of A, B1, B2 and C carbohydrate fractions presented between 2.73 and 5.44%; 1.91 and 2.35%; 77.49 and 80.59%, and, 13.59 and 17.87%, as a percentage of total carbohydrates, in hays with ages between 28 and 56 days of regrowth. The degradation rate of the A + B1 and B2 carbohydrate fractions presented between 0.181 and 0.20, and 0.04 and 0.0466 h -1, in hays with ages between 28 and 56 days of regrowth, respectively.

A gas-phase surface sol–gel process was developed for facile preparation of ultrathin TiO2 gel/Cyt. c multilayered films. Positively charged Cyt. c protein was alternately assembled with TiO2 gel l...

Electroporation was used as a powerful and simple method to probe to the intracellular distribution and trafficking of signal sequences. By coupling synthetic peptides to carrier reporter groups, specific amino acid sequences responsible for nucleolar targeting of Semliki Forest virus (SFV) Core (C) protein were found out. In the N-terminal part of the C protein the sequences 66KPKKKKTTKPKPKTQPKK83 92KKKDKQADKKKKP105 are able to situate BSA or KLH as reporter proteins in the nucleolus, suggesting that SFV C protein contains at least two independent nucleolar targeting sequences.

Myosin filaments were prepared by either dialysis or rapid dilution to give a final condition of 0.1 m KC1 and pH 6.0, in the presence or absence of C-protein. The average length of myosin filaments prepared by dialysis was much longer than that by dilution whether C-protein is present or absent. C-protein reduced the diameters of both filaments but no significant effects on the filament length were observed. All of the myosin filament suspensions formed gels upon heating, but C-protein alone did not. The strengths of thermal gels of myosin filaments prepared by dialysis were much higher than those'by dilution. In addition, a fine strand-like network structure was formed in the gel from dialyzed myosin, but diluted myosin formed a rather coarse network structure. C- protein lowered the strengths of thermal gels of myosin filaments, especially that prepared by dialysis. These results suggest that the rheological properties of thermal gels of myosin filaments at low ionic strength depend on the structure of...

Mouse A-9 cells infected with the minute virus of mice were found to have DNA-containing particles of two densities when centrifuged to equilibrium in CsCl, as well as particles which contained no detectable DNA. The DNA-containing heavy particles (1.47 g/cc) were converted to the light particles (1.42 g/cc) after one round of infection when left in the infected cell culture. The light particles had about a fivefold higher hemagglutinating activity than the heavy particles. The only difference in composition detected between the heavy and light particles was in the structural proteins. Sodium dodecyl sulfate (SDS)-polyacrylamide-gel electrophoresis resolved three proteins in the minute virus of mice particles: A protein (92,000 daltons), B protein (72,000 daltons) and C protein (69,000 daltons). The A protein was found in about the same number of molecules in all particles. The empty particles and the heavy particles had B as the major capsid protein, while the light particles had C as the major capsid protein.

C-protein has previously been shown to bind to the light-meromyosin region of the myosin tail. Examination of mixtures of C-protein with heavy meromyosin or subfragment-2 or subfragment-1 in the analytical ultracentrifuge shows that there is also a binding site for C-protein in the subfragment-2 region of the tail.

Salmonella typhimurium was shown to contain a citrate-binding protein (C protein) which was purified to homogeneity from the periplasmic fraction released by cold osmotic shock. The protein is dimeric, has an apparent molecular weight of 28 000 and an isoelectric point of 6.1. Sodium ions were required for optimum substrate binding, however, the divalent cations Zn2+, Mg2+, and Co2+ were inhibitory. The C protein was relatively stable but sensitive to various detergents and chaotropic agents. Approximately one citrate molecule was bound per molecule of protein and citrate binding (Kd = 1–2.6 μM) was strongly competitively inhibited by DL-isocitrate and DL-fluorocitrate but not by other carboxylates. Neither succinate, glutamate, nor acetate were bound to the C protein. No apparent enzyme activity was associated with this protein. A concomitant reduction in the level of binding protein and in citrate transport activity occurred in osmotically shocked cells as well as with L-malate- or succinate-grown cells. Fluorocitrate-resistant mutants were simultaneously defective in citrate transport, citrate binding, and production of cross-reacting material. One transport-defective mutant did produce citrate binding protein.

The plasma decay of three groups of iodinated apoproteins on human very low density lipoproteins were evaluated in two normals, two subjects with endogenous hypertriglyceridemia and another two with dysbetalipoproteinemia. The apo beta decay was more rapid than that of the C apoproteins in all patients. The apo beta decay was more rapid for the normals than for either the subjects with hypertriglyceridemia or dysbetalipoprotenemia. The apo C protein had an irregular decay in the normals but decayed less irregularly for the hypertriglyceridemics. The arginine rich apoprotein had a decay somewhat similar to apo C protein in the normals. The apo beta protein of the α 2 very low density lipoprotein of a dysbetalipoproteinemic was consistent with a precursor relationship to the apo beta of beta very low density lipoprotein of this subject, but the arginine rich apoprotein was not.

Two experiments were conducted to study the protein and amino acid requirements of growing Large White female turkeys at temperatures of 7, 14, 21, and 28 C. In Experiment 1, five dietary treatment series (A, B, C, D and E) which ranged in protein content from 24.3 to 16.9, 20.4 to 14.2 and 17.8 to 11.9%, were fed during 8 to 11, 11 to 14, and 14 to 17 wk of age, respectively. The D diet series was also supplemented with methionine or lysine or both to equal the levels in the B series forming the D, DM, DL, and DML treatments. In Experiment 2, B and C protein levels were fed between 11 and 14 wk of age. Between 14 and 17 wk of age, the B, C, D, and E protein levels were fed to each group forming a 2 X 4 factorial arrangement. In Experiment 1, during 8 to 11 wk of age, body weight gain decreased when birds were fed diets containing less than 22.5% protein. From 11 to 14 wk of age, at 7 and 14 C, the C diet supported maximum gains but at 21 and 28 C, the B and A diets, respectively, resulted in heavier turkeys. With the D diet, methionine supplementation significantly (P less than .05) improved body weight of birds during 8 to 11 and 11 to 14 wk of age: lysine supplementation had no effect during 8 to 11 wk and inconsistent effects on gain during 11 to 14 and 14 to 17 wk of age. Results from 14 to 17 wk of age show that the protein requirement of female turkeys during this age was overestimated by the National Research Council in 1984.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluorescence spectra of ANM-labeled, glycerinated rabbit psoas muscle fibers were recorded in relaxed, contracted, and rigor states. SDS polyacrylamide gel electrophoresis of the ANM-labeled muscle fibers indicated that proteins labeled with ANM were myosin heavy chain, C protein, and actin. In a relaxed state in the presence of ATP, myosin heavy chain was mainly labeled. During the transition from rigor to the relaxed or contracted state, there was a blue shift (about 5 nm) of the ANM emission spectrum. Similar experiments with FAM (N-(3-fluoranthyl)-maleimide)-labeled muscle fibers showed that these fluorescence changes were not artifacts due to the movement of muscle fibers. The fibers labeled in the ATP relaxing solution showed a marked decrease in both isometric force and unloaded shortening velocity (Vo), while in the fibers labeled in the rigor solution isometric tension was not markedly suppressed, though Vo decreased to the same extent as in the fibers labeled in the ATP relaxing solution. Fluorescence spectra of ANM-labeled HMM in different states were also measured. A fluorescence enhancement and a blue shift (about 5 nm) of the emission maximum were observed in HMM + MgATP or HMM + MgATP + F-actin in comparison with HMM + F-actin. These results suggest that the fluorescence spectra of the ANM-labeled muscle fibers reflect their conformational changes between the rigor state (in the absence of MgATP) and the relaxed or contracted state (in the presence of MgATP).

The Raman spectra of purified myosin, C-protein and myosin-C-protein complex in aqueous solution, as well as that of pelleted filaments, were analyzed. The analyses confirmed that C-protein adopts a predominantly non-alpha-helical structure, while myosin adopts a predominantly alpha-helical structure. Neither 10 mM MgCl2 nor filament formation induced large conformational changes of purified myosin. Thermal denaturation of purified myosin, however, induced large changes in the Raman spectrum owing to conformational changes. It is likely that the binding of myosin and C-protein is not accompanied by large conformational changes of the proteins.

Antibody labeling for C-protein observed in fluorescence microscopy shows that C-protein is located only in the middle one-third of each half of the A-band. In electron microscopy the labeling shows up as stripes spaced 430apart. The restricted location of C-protein to these stripes cannot be determined by electron microscopy alone. The earlier assumption that the stripes reflect the axial repeat of the myosin in the myosin filament ( Pepe, 1967 a ) is valid, since C-protein binds to the filaments with the repeat of the underlying molecules ( Pepe et al. , 1975 ; Rome et al. , 1973 ; Pepe, 1972 ). The labeling pattern for C-protein occurs in the same position as part of the labeling pattern for myosin. This explains why similar anti-myosin labeling patterns are observed in fluorescence microscopy regardless of the presence or absence of contaminating antibody to C-protein. In electron microscopy the labeling patterns are clearly different. This can be explained by the difference in detectability of antibody protein in fluorescence and electron microscopy. The antibody labeling experiments show that proteins other than C-protein are also present on the myosin filaments. Although antibody to these other proteins is detectable by antibody labeling, it is not detectable by immuno-diffusion against even the initial crude myosin extract.

The influence of feeding supplemental vitamin C was determined on dietary protein level and upon protein patterns of serum and egg albumen and on egg quality from hens of different ages and strains. One-year-old Single Comb White Leghorn (S.C.W.L.) strain A hens were randomly assigned to either a 15% protein basal layer ration with or without a 3300 p.p.m. vitamin C supplement. Two-, four- and seven-year-old S.C.W.L. strain A hens and two-year old S.C.W.L. strain B hens were assigned to either a 15% or an 18% protein diet with or without supplementation of 1322 p.p.m. vitamin C. Egg production was significantly (P Shell thickness was significantly (P

THE X-ray diffraction pattern of vertebrate skeletal muscle contains a meridional reflexion at 442 A which has been attributed to an unknown component of the thick filament with a periodicity different from that of the myosin structure1,2. Using a new approach combining immunological and X-ray diffraction techniques, we have found that C-protein, a recently discovered myofibrillar protein located in the thick filaments3–5, contributes to the 442 A reflexion. We interpret the X-ray data in a new way, and suggest that C-protein and myosin may have the same periodicity in the thick filament.

In bacteriophage lambda, genes C and Nu3, two of the four cistrons which are essential for normal prohead formation, have overlapping nucleotide sequences. These genes are translated in the same reading frame so that the Nu3 protein is identical to the COOH-terminal one-third of the C protein. This structural relationship may provide for the functional interaction of the C and Nu3 proteins through their regions of structural homology during prohead assembly. The in-phase overlapping organisation of genes may constitute a general strategy to facilitate the mutual interaction of a pair of proteins through their common structural domains.