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A well-structured in silico workflow is here reported for disclosing structure-based pharmacophore models against bromodomain-containing protein 9 (BRD9), accelerating virtual screening campaigns and facilitating the identification of novel binders. Specifically, starting from 23 known ligands co-crystallized with BRD9, three-dimensional pharmacophore models, namely placed in a reference protein structure, were developed. Specifically, we here introduce a fragment-related pharmacophore model, useful for the identification of new promising small chemical probes targeting the protein region responsible of the acetyllysine recognition, and two further pharmacophore models useful for the selection of compounds featuring drug-like properties. A pharmacophore-driven virtual screening campaign was then performed to facilitate the selection of new selective BRD9 ligands, starting from a large library of commercially available molecules. The identification of a promising BRD9 binder (7) prompted us to re-iterate this computational workflow on a second focused in-house built library of synthesizable compounds and, eventually, three further novel BRD9 binders were disclosed (8-10). Moreover, all these compounds were tested among a panel comprising other nine bromodomains, showing a high selectivity for BRD9. Preclinical bioscreens for potential anticancer activity highlighted compound 7 as that showing the most promising biological effects, proving the reliability of this in silico pipeline and confirming the applicability of the here introduced structure-based three-dimensional pharmacophore models as straightforward tools for the selection of new BRD9 ligands.

Advances in genetic manipulation have allowed the overexpression of proteins and insertion of circuits in cells. However, the expected behaviour can be altered by the internal competition for the limited amount of cellular resources. In this work we analyse a feedback strategy based on transcription inhibition that aims to reduce the interaction in a two-protein expression system. The results allow interpreting the effects of negative feedback on the steady-state protein levels and how the realizable protein region is affected by the feedback loop. Fil: Nuñez, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; Argentina Fil: Garelli, Fabricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; Argentina Fil: Picó, Jesús. Universidad Politécnica de Valencia. Departamento de Ingeniería de Sistemas y Automática; España Fil: de Battista, Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; Argentina

Understanding protein-ligand interactions is crucial to drug discovery and design. However, it would be extremely difficult for the proteins which only have one available apo structure but multiple binding sites. To address this constraint, a fragment-centric topographic mapping method (AlphaSpace software) was employed to map out concave interaction pockets at the assigned protein region. These pockets are used as complementary spaces to screen the known inhibitors for this specific binding site and to guide the molecular docking pose selection as well as protein-ligand interaction analysis. By mapping the shape of central cavity surface, we have tested the strategy against a multi-drug resistant transmembrane protein-ABCG2 to assist in generating a pharmacophore model for its inhibitors that is based on the structure of apo. Classical molecular simulation and accelerated molecular simulation are used to verify the accuracy of inhibitor screening and binding pose selection. Our study not only has gained insight for the development of novel specific ABCG2 inhibitors, but also has provided a general strategy in describing protein-ligand interactions.

Unraveling the role of post-translational modification (PTM) patterns is one of the most urgent and unresolved issues facing the scientific community. Attempts to crack the phosphorylation bio-barcode led to significant findings, which suggest that many proteins cannot be regarded as a single entity but exist as several forms which differ in their phosphorylation patterns and their functions. While protein regions that do not contain PTMs can be rather simply mimicked using peptide libraries, heavily phosphorylated regions are much harder to study using the same tools. The differences between the syntheses of simple mono-, di- and tri-phosphopeptides and the synthesis of multiphosphopeptides are dramatic. While simple phosphopeptides can be synthesized using almost standard SPPS strategies, the synthesis of multiphosphopeptides is to date a major synthetic challenge. Synthesis of multiphosphopeptides requires the insertion of several phosphate groups simultaneously or sequentially into various positions on the peptide in the presence of many other potential modification sites. These groups are bulky, unstable and cannot be easily introduced when in close proximity. Moreover, since the same protein region can possess many alternative multiphosphorylation patterns, libraries comprising a large number of peptides with different degrees and positions of phosphorylation are essential. Many strategies have been developed to provide routes to enable the preparation of multiphosphopeptides. These methods are essentially different from the methods used for the preparation of simple phosphopeptides. In this review, we specifically emphasize the challenges and importance of synthesizing multiphosphopeptides and their libraries. The historical perspective and state of the art strategies are described. We demonstrate here how the different synthetic approaches attempt to address the special problems associated with the synthesis of multiphosphopeptides. The advantages and disadvantages of each strategy are discussed in order to provide a roadmap for the synthesis of such libraries. An overview of the existing strategies and some comments regarding future directions are provided. Applications of multiphosphopeptide libraries as tools to study the effect of phosphorylation patterns on the biological function of proteins are also described.

Human tyrosine hydroxylase 1 (hTH1) activity is regulated by phosphorylation of its regulatory domain (RD-hTH1) and by an interaction with the 14-3-3 protein. The RD-hTH1 is composed of a structured region (66-169) preceded by an intrinsically disordered protein region (IDP, hTH1_65) containing two phosphorylation sites (S19 and S40) which are highly relevant for its increase in activity. The NMR signals of the IDP region in the non-phosphorylated, singly phosphorylated (pS40) and doubly phosphorylated states (pS19_pS40) were assigned by non-uniformly sampled spectra with increased dimensionality (5D). The structural changes induced by phosphorylation were analyzed by means of secondary structure propensities. The phosphorylation kinetics of the S40 and S19 by kinases PKA and PRAK respectively were monitored by non-uniformly sampled time-resolved NMR spectroscopy followed by their quantitative analysis.

Accurate prediction of intrinsically disordered proteins/regions is one of the most important tasks in bioinformatics, and some computational predictors have been proposed to solve this problem. How to efficiently incorporate the sequence-order effect is critical for constructing an accurate predictor because disordered region distributions show global sequence patterns. In order to capture these sequence patterns, several sequence labelling models have been applied to this field, such as conditional random fields (CRFs). However, these methods suffer from certain disadvantages. In this study, we proposed a new computational predictor called IDP&ndash, CRF, which is trained on an updated benchmark dataset based on the MobiDB database and the DisProt database, and incorporates more comprehensive sequence-based features, including PSSMs (position-specific scoring matrices), kmer, predicted secondary structures, and relative solvent accessibilities. Experimental results on the benchmark dataset and two independent datasets show that IDP&ndash, CRF outperforms 25 existing state-of-the-art methods in this field, demonstrating that IDP&ndash, CRF is a very useful tool for identifying IDPs/IDRs (intrinsically disordered proteins/regions). We anticipate that IDP&ndash, CRF will facilitate the development of protein sequence analysis.

The objective of this study was to evaluate the prevalence, genotypic characterization, and determination of the patterns of shedding of human polyomavirus JC (JCPyV) and BK (BKPyV) in consecutive urine samples collected from healthy adults. Urine samples collected monthly over a 6 month period were screened by polymerase chain reaction (PCR) with two sets of primers complementary to the VP1 protein region specific for the JCPyV or BKPyV genome. The viral load of JCPyV and BKPyV in positive samples was determined by quantitative real time PCR. Seventy-one healthy individuals (ages between 18 and 65) were included in the study. Polyomavirus DNA urinary shedding was identified in 44 (62%) of the 71 individuals evaluated: BKPyV only in 16 (22.5%); JCPyV only in 19 (26.7%); and both in 9 (12.7%). Among the 28 individuals shedding JCPyV, the shedding was nearly continuous in 13 (46.4%) and sporadic in 15 (53.6%), whereas all BKPyV shedding was sporadic. A total of 45 (19 BKPyV and 26 JCPyV) strains were identified. Of the BKPyV strains, individuals were observed that excreted all genotypes except genotype 3 and the JCPyV strains, excretion of 5 different genotypes. Evaluating the age of individuals who excrete JCPyV and BKPyV, mostly are young adults, with a slight increase with increasing age and observing the viral load can not draw any parallel between the increase or decrease of age or excreted genotype as there was a wide variation both in the excretion of BKPyV and JCPyV. The high occurrence of isolated or simultaneous urinary shedding of JCPyV and BKPyV in healthy individuals merits further study. J. Med. Virol. 88:153–158, 2016. © 2015 Wiley Periodicals, Inc.

Wheat spindle streak mosaic virus is a Bymovirus transmitted by the plasmodiophorid Polymyxa graminis that infects small grains such as wheat, rye and triticale. Nucleotide sequences of WSSMV isolates from several locations in Germany used for virus resistance trials differ from the sequences of the isolates found in France, Denmark, and the USA by a nona-nucleotide insertion in the 14K protein region.

Superabsorbent pads are composed of different layers with different grades of absorbent capacity, being the lower one the most absorbent layer. Due to their complexity, the analysis of bodily fluids on superabsorbent pads is certainly difficult. In this study, semen, vaginal fluid and urine stains placed on superabsorbent pads including sanitary napkins, panty-liners and diapers were non-destructively detected by Attenuated Total Reflectance (ATR) Fourier Transform Infrared spectroscopy (FTIR). In spite of the higher absorbent capacity of the lower layers, this technique was able to detect the three fluids on the upper layer of all pads, showing that bodily fluids are distributed within all layers. Additionally, mixtures of these bodily fluids prepared on superabsorbent pads and cotton were studied, since real forensic investigations involving sexual abuse cases usually deal with mixtures of these fluids. Due to their IR marked protein region (1800-1480 cm-1), semen and vaginal fluid were easily distinguished from urine. However, since semen and vaginal fluid have both a high protein composition, that region of their IR signatures were quite similar, except for slight visual differences, that should be further analysed. Therefore, we propose ATR-FTIR as a suitable, presumptive, non-destructive and rapid approach to detect stains of human bodily fluids on the upper layer of superabsorbent pads from sexual crimes.

Permeation enhancer strategy is used to develop Benzoylaconitine (BA) of high molecular weight (603.7 Da) into transdermal patch. The present study was to achieve a patch with good analgesic and anti-inflammatory effects and investigate the relationship between physicochemical parameters of enhancers and enhancement strength. In vitro skin permeation study was used to evaluate the effect of enhancers, and correlation study was conducted to clarify the relationship between physicochemical parameters of enhancer and permeation amount. The enhancement molecular mechanism was characterized using FT-IR and molecular modeling. Finally, pharmacodynamic effect of BA patch was evaluated with analgesic and anti-inflammatory assessment. The correlation analysis indicated that the optimized patch containing permeation enhancer Plurol® Oleique CC497 with high surface tension (43.0 dyne/m), demonstrated the strongest skin permeation amount of 5.50 ± 0.21 μg/cm2. According to the FT-IR and molecular modeling study, the enhancer with high surface tension demonstrated maximum interaction strength (Emix = −9.20 kcal/mol) with skin lipid and affected the skin protein region, which strongly disturbed skin lipid arrangement according to the results of ATR-FTIR study (wavenumber variation of νas CH2 of skin lipid > 2.00 cm−1) and molecular modeling (Cohesive Energy Density of skin lipid bilayer = 1.04E + 08 kcal/mol). It was indicated that only based on sufficient interaction strength and disturbing of both lipophilic and hydrophilic area of stratum corneum, permeation enhancer was able to demonstrated great permeation enhancement effect. Finally, BA transdermal patch was developed and showed excellent analgesic and anti-inflammatory effect, which was a potential preparation for the treatment of inflammatory pain.

Bats have great potential as reservoirs for emerging viruses such as severe acute respiratory syndrome-coronavirus. In this study, bat coronaviruses (BtCoVs) were detected by RT-PCR from intestinal and fecal specimens of Miniopterus fuliginosus breeding colonies in Wakayama Prefecture caves, where we previously identified bat betaherpesvirus 2. Two primer sets were used for the detection of BtCoV: one was for the RNA-dependent RNA polymerase (RdRp) region and the other was for the spike (S) protein region. Eleven and 73% of intestinal and fecal specimens, respectively, were positive for RdRp region, and 2 and 40% of those were positive for S protein region. Sequencing and phylogenetic analysis showed that the detected BtCoV belonged to the group 1 (alpha) coronaviruses. These data suggest that BtCoV is endemic in M. fuliginosus in Japan.

The Melanophila acuminata beetle is attracted to forest fires via a pair of infrared sensory organs composed of sensilla. Our histological work showed that each sensillum contains lipid layers surrounding a protein layer and a unique polysaccharide base that is associated with a neuron to each sensillum. Infrared microscopy showed that the protein region maximally absorbs infrared radiation at 3 μm wavelength and at 10 μm, which corresponds to the known radiation produced by forest fires at 3 μm. Mathematical calculations showed that the physical properties of the sensilla are such that the expected temperature rise is insufficient for transduction of the infrared signal through mechanical means or as a thermal receptor as previously thought; hence the protein plays the pivotal role in perception of single photons and transmission of the signal within the sensilla.

Twelve samples of cheeses (three types of Saint-Nectaire PDO cheeses and Savaron cheeses) differing by manufacturing and ripening conditions, from 12 different producers, were characterised by attenuated total reflectance mid-infrared (MIR) and front-face fluorescence spectroscopies, dynamic testing rheology and physico-chemical analysis. Fluorescence spectra (tryptophan residues, vitamin A and riboflavin) and MIR (3,000–2,800 (fat region), 1,700–1,500 (protein region) and 1,500–900 cm−1 (fingerprint region)) spectra were recorded on cheese samples. The potential of the data tables was investigated for discriminating the four different groups of cheeses. The results of factorial discriminant analysis (FDA) performed on the fluorescence and mid-infrared spectra showed a good discrimination of the four cheese groups. Considering cross-validation results, the best classifications (100%) were achieved from mid-infrared and fluorescence spectra, while only 91.7 and 72.2% of correct classification were obtained by applying FDA to rheology and physico-chemical data, respectively. Spectroscopic techniques could provide useful fingerprints and allow the identification of investigated cheeses according to manufacturing conditions. Simple and rapid spectroscopic methods offer a promising approach to the authentication of cheeses.

Intrinsically disordered proteins (IDPs) constitute a recently recognized realm of atypical biologically active proteins that lack stable structure under physiological conditions, but are commonly involved in such crucial cellular processes as regulation, recognition, signaling and control. IDPs are very common among proteins associated with various diseases. Recently, we performed a systematic bioinformatics analysis of the human diseasome, a network that linked the human disease phenome (which includes all the human genetic diseases) with the human disease genome (which contains all the disease-related genes) (Goh, K. I., Cusick, M. E., Valle, D., Childs, B., Vidal, M., and Barabasi, A. L. (2007). The human disease network. Proc. Natl. Acad. Sci. U.S.A. 104, 8685-90). The analysis of this diseasome revealed that IDPs are abundant in proteins linked to human genetic diseases, and that different genetic disease classes varied dramatically in the IDP content (Midic U., Oldfield C.J., Dunker A.K., Obradovic Z., Uversky V.N. (2009) Protein disorder in the human diseasome: Unfoldomics of human genetic diseases. BMC Genomics. In press). Furthermore, many of the genetic disease- related proteins were shown to contain at least one molecular recognition feature, which is a relatively short loosely struc- tured protein region within a mostly disordered segment with the feature gaining structure upon binding to a partner. Fi- nally, alternative splicing was shown to be abundant among the diseasome genes. Based on these observations the human- genetic-disease-associated unfoldome was created. This minireview describes several illustrative examples of ordered and intrinsically disordered members of the human diseasome.

Endometrial carcinoma consists of endometrioid (type I) and serous papillary (SP; type II) subtypes; a rarer form is malignant mixed mullerian tumours (MMMT; type II/mixed). We set out to determine whether one might be able to biochemically signature these subtypes using Fourier-transform infrared (FTIR) microspectroscopy and distinguish non-tamoxifen associated from tamoxifen-associated cases. Paraffin-embedded blocks were obtained from non-tamoxifen associated cases reported as endometrioid (n=7), SP (n=4) or MMMT (n=4). From tamoxifen-associated cases, endometrioid (n=1), SP (n=3) and MMMT (n=4) blocks were retrieved; benign tissues (n=3) were also analysed. Exploiting synchrotron-based radiation, sections (10-microm thick) on BaF(2) windows were interrogated through a 10 microm x 10 microm aperture. Point spectra were derived from >or=10 locations in each of six glandular elements per tissue; a further 20 stromal spectra were obtained. Following normalisation to Amide I, average spectra (1800-900 cm(-1)) per gland or stroma were analysed for variance using principal component analysis (PCA) and linear discriminant analysis (LDA). In scores plots, segregation of spectra from different subtypes or benign tissues was noted and it proved possible to distinguish tamoxifen-associated cases. In the PCA-LDA loadings plots, the wavenumbers that highlighted variance for benign or endometrioid carcinoma tissues were in the protein region (1800-1480 cm(-1)) whereas those contributing most to SP or MMMT segregation were primarily in the DNA/RNA region (1425-900 cm(-1)) of the vibrational spectrum. Our results suggest that the application of FTIR microspectroscopy is a powerful new approach in disease diagnosis and characterisation.

Black box modelling is used here to improve the performances of the PoPMuSiC program that predicts protein stability changes caused by single-site mutations. For that purpose previously developed statistical energy functions are exploited, which are based on a formalism that highlights the coupling between 4 different protein descriptors (sequence, distance, torsion angles and solvent-accessibility), as well as the volume variation of the mutated amino acid. As the importance of the different types of interactions may depend on the protein region, the stability change is expressed as a linear combination of these energetic functions, whose proportionality coefficients vary with the solvent-accessibility of the mutated residue. Two alternative structures are considered for these coefficients: a Radial Basis Function network, and a MultiLayer Perceptron with sigmoid nodes. These two structures are identified, leading to an improvement of the predictive capabilities of PoPMuSiC, and are discussed in terms of their biophysical interpretation.

Analysis of the intensely studied HIV-1 gp120 V3 protein region reveals that the among-population mean site-specific frequency of an amino acid is a measure of its relative marginal fitness. This surprising result may arise if populations are displaced from mutation–selection equilibrium by fluctuating selection and if the probability of fixation of a beneficial amino acid is proportional to its selection coefficient.

A series of glycosyl serines 1–6 which are located in the carbohydrate-protein linkage region of proteoglycans, including the chondrottin penta- and heptasaccharides GalNAcα(1–4)R (3), GalNAcs(1–4)R (4) and GalNAcs(1–4)GlcAs(1–3)GalNAc(1–4)R (6) as well as the heparin pentasaccharide GlcNAcα(1–4)R (5) [R = GlcAs(1–3)Gals(1–3)Gals(1–4)Xyls-Ser] were systematically synthesized as follows. Trisaccharide acceptor 27 having a Gal(1–3)Gals(1–4)Xyl sequence was glycosylated with di- and tetrasaccharide donors 16α, 16s, 22, and 26, which correspond to the non-reducing end sequences of 3–6, regio- and stereoselectively to afford penta- and heptasaccharides 30, 34, 36, and 39, respectively. After the conversion into the respective penta- and heptaosylimidates 42c-f as well as tri- and tetraosylimidates 42a and b, they were coupled with serine derivative 43 to give tri-, tetra-, penta-, and heptaosyl serines 44a-f. All the glycosyl serines were deprotected to 1–6.

Cytoplasmic S4‐S5 loops have been shown to be involved in fast inactivation of voltagegate di on channels. We studied mutations in these loops and their potential cooperative effects in domains D3 (N1151C, A1152C, I1160C/A) and D4 (F1473C, L1482C/A) of the human skeletal muscle Na + channel α-subunit (hNav1.4) using expression in tsA201 cells and the whole cell patch-clamp technique. All cysteine mutations were accessible to intracellularly applied sulfhydryl reagents which considerably destabilized fast inactivation. For different combinations of corresponding D3/D4 double mutations, fast inactivation could be almost completely removed. Thermodynamic cycle analysis indicated an additive effect for N1151C/F1473C and a significant cooperative effect for I1160/L1482 double mutations. Application of oxidizing reagents such as Cu-phenanthroline to link two cysteines via a disulfide bridge did not reveal evidence for a direct physical interaction of cysteines in D3 and D4. In addition to the pronounced alterations of fast inactivation, mutations of I1160 shifted steady-state activation in the hyperpolarizing direction and slowed the kinetics of both activation and deactivation. Sulfhydryl reagents had charge-dependent effects on I1160C suggesting interaction with negative charges in another protein region. We conclude that fast inactivation of the Na + channel involves both S4‐S5 loops in D3 and D4 in a cooperative manner. D3/S4‐S5 also plays an important role in activation and deactivation.

Given the necessity for increased conservation of endangered birds such as the Crested ibis, it is crucial to identify the gender of individuals fro m species with similar external mo rphologies among females (ZW) and males(ZZ) to establish a self-sustainable population for restoration of the species. Moreover, raising young chicks during the juvenile period based on sex determination encourages familiarity, wh ich might increase mating success rates. Thus, this study was carried out to determine the sex of Crested ibis chicks using three primers designed to check their identity. A se t of poly- merase chain reaction(PCR) primers was used to amplify a 276 bp chro mo-helicase-DNA b inding protein region(CHD) on the Z chro mosome in both sexes, whereas the other set was used to amp lify a 169 bp female -specific CHD sequence on the W chromosome. The sequences have been submitted to NCBI(GenBank Accession Number: AB620020, AB620021). Th is method will enable researchers to determine the gender of Crested ibis more simp ly and quickly.

Over 500 researchers participated in a recent American Association for Cancer Research special conference, entitled “Apoptosis and Cancer: Basic Mechanisms and Therapeutic Opportunities in the Post-Genomic Era” (February 13–17, 2002) in sunny Hawaii (Hilton Waikoloa village, Kona, Hawaii). The meeting participants presented the most recent findings on the mechanisms regulating cell death in cancer. In the past decade, apoptosis research has undergone a quantum leap, metamorphosing from a descriptive, phenomenological discipline into a molecularly defined, highly complex signalling field. This transformation was highlighted in the conference's opening talk by meeting co-organizer, John Reed (The Burnham Institute, La Jolla, CA). Reed and colleagues used published protein functional information and bio-informatic mining of the available human genome databases to tabulate the number of human proteins predicted to be involved in regulating apoptosis. The list includes 11 catalytically active caspases, 26 CARD (caspase associated recruitment domain)-, 32 DD (death domain)-, 12 DED (death effector domain)-, 8 BIR (baculovirus inhibitor of apoptosis protein region)-, 24 BH (Bcl-2 homology)-, and 34 PAAD/PYD (pyrin/PAAD)-containing sequences.

Mitogenic activity and antitumor activity of Aloe arborescens Miller, Aloe barbadensis Miller and Aloe africana Miller, which have been used as traditional drugs and health food, were studied. The raw fresh aloe was divided into flesh and skins, and was lyophilized. Fraction were obtained by extraction with hot water, 0.1M NaOH and 0.5M NaOH. Mitogen assay was performed for all fraction using spleen cells from mice (_??_), C3H/HeN and C3H/HeJ. Six fractions showed mitogenic activity towards spleen cells of C3H/HeN. In addition, although the proteins were removed with actinase, the samples continued to show this activity. Among them, the non-dialyzable fraction of hot water extracts from a skin of Aloe arborescens Miller and the non-dialyzable fraction of hot water extracts from a skin of Aloe africana Miller showed strong mitogenic activity towards cells of C3H/HeJ, suggesting that it was free from bacterial endotoxic lipopolysaccharide. These results suggest that the activity components are not located in the protein region. No fraction showed antitumor activity against Sarcoma 180 ascites in mice.

In spite of the high similarity in amino acid sequence between rod visual pigment rhodopsin and gecko blue-sensitive pigment (gecko blue), not only the spectral sensitivities but also the thermal decay rates of the meta II- and III-intermediates are noticeably different from one another [Kojima et al. (1995) Biochemistry 34, 1096-1106]. In order to identify the protein region(s) that contain(s) key residue being responsible for the functional difference, we constructed six chimerical mutants derived from gecko blue and bovine rhodopsin, with the aid of protein production in a human embryonic kidney cell line (293S). While the absorption maximum of every mutant was located in between gecko blue (466 nm) and bovine rhodopsin (500 nm), a large blue-shift (18 nm) was observed when the helices I-III of rhodopsin were replaced with those of gecko blue. A time resolved spectroscopic study demonstrated that this replacement also accelerated the decay rate of the meta II-intermediate. The decay of the meta III-intermediate of the mutants became faster as the compartment of gecko blue was increased. Thus, the faster decay of the meta II-intermediate of gecko blue is largely attributed to residues within helices I-III, while the decay of the meta III-intermediate apparently depends on the overall structure of the protein.

Detection of Capsicum chlorosis virus (CaCV), An Emerging Virus Infecting Chilli in Tamil Nadu, India Chilli plants in the farmers’ fields in Tamil Nadu showing symptoms of concentric chlorotic and necrotic rings on the leaves were found infected with a tospo virus through RT- PCR by using tospo virus degenerate primer (gL3637 /F and gL4435C). From the BLAST result the virus associated with the disease is identified as Capsicum chlorosis virus (CaCV). For further confirmation, infected samples collected from Coimbatore were amplified using newly designed primer pair (GKCaCVCPF1/R1) corresponding to the nucleocapsid region of the CaCV for further confirmation. In the sequence analysis, complete nucleocapsid protein region shared a nucleotide and amino acid identity of 99.1% and 100% with the PB4 and PB1 isolates of CaCV from India respectively. In the phylogenetic analysis, this isolate grouped with the CaCV isolates from Aurangabad and Tamil Nadu, India than with isolates from other countries. About fifteen hosts from different families were inoculated through sap, of which nine hosts produce local lesion and four showed systemic symptoms. The positive reaction of extract from these plants in DAS- ELISA (double antibody sandwich ELISA) against the Nucleocapsid protein of CaCV (DSMZ, Germany), confirmed the presence of CaCV in infected chilli plants in Tamil Nadu..

It is clear now that proteins lacking ordered structure, generally known as intrinsically disordered proteins (IDPs), possess numerous biological functions that complement functional repertoires of ordered proteins. IDPs are common in nature, and abundantly found to be involved in the pathogenesis of various diseases. These proteins participate in various biological processes and play crucial roles in regulation of functions of their binding partners. Often, disorder-to-order transition induced by the IDP binding to a specific partner defines the low-affinity - high-specificity signaling interactions. Although many IDPs undergo a disorder-to-order transition upon binding, large fraction of IDPs can preserve significant amount of disorder even in their bound states. IDPs can participate in one-tomany and many-to-one interactions, where one intrinsically disordered protein region (IDPR) binds to multiple partners potentially gaining very different structures in the bound state, or where multiple unrelated IDPs/IDPRs bind to one partner. Binding functions of IDPs and IDPRs are controlled by various means, such as numerous posttranslational modifications and alternative splicing. Some of the aspects of the intrinsic disorder-based protein interactions and modes of their regulation are considered in this review.

Aim: To detect gestational diabetes mellitus biomarkers in human amniotic fluid collected for age-related genetic testing using capillary electrophoresis and a sophisticated data analysis methodology. Materials & methods: Amniotic fluid samples were separated by capillary electrophoresis. Samples were classified using a genetic algorithm with Bayesian benefit function. The best model maximized the sensitivity and specificity and employed a leave-one-out cross-validation strategy. Results: Gestational diabetes mellitus (GDM; n = 14) was distinguished from non-GDM (n = 95) with 86% sensitivity and 99% specificity using two wavelets. These wavelets were located in the unresolved protein region and on the edge of the maternally derived albumin peak. Conclusion: GDM is a maternal pathology; however, it was shown that it alters the biochemical profile of amniotic fluid. Testing for GDM is normally carried out at 24–28 weeks, but changes can be detected at 15 weeks gestation, suggesting that GDM onset occurs early in gestation.

55 accessions of wild peanuts (Arachis spp.) introduced from South America were analyzed for seed storage protein composition using SDS-PAGE electrophoresis. The objectives of the study were to evaluate variability within sect.Arachis and to classify taxa based on protein composition. 25 different band positions were resolved. Individual accessions had 11 to 18 bands which included the conarachin region (MW > 50 kD), two to five bands in the acidic arachin region (MW 38–49.9 kD), three to seven in the intermediate MW region (23 to 37.9 kD), two to five bands in the basic arachin region (18–22.9 kD), and one to three bands in the low MW protein region (14–17.9 kD). These data were utilized in a principal coordinate analysis based on the matrix of genetic distances between all pairs of the 55 accessions. Several groups of accessions conformed to expected species classification includingA. batizocoi, A. stenosperma, andA. monticola; whileA. duranensis, A. cardenasii, A. helodes, andA. correntina did not form good groups. The study showed that great diversity exists for protein profiles and seed storage proteins have potential for aiding species classification and for serving as markers for interspecific hybridization studies.

We identified two BRCA1 mutations in a high risk breast cancer family: the missense 1240 C>T (Thr>Ile) and the 1241delAC at codon 374, which results in a stop at codon 376. Both were contiguously located in the same BRCA1 gene, in a motif of 11 amino acids, which is highly conserved across human, canine and murine species. The presence of missense mutations in this motif in breast-cancer families suggests an important functional role for this protein region and a potential deleterious effect of the 1240C>T mutation.

Motivation: Protein–protein interactions are commonly mediated by the physical contact of distinct protein regions. Computational identification of interacting protein regions aids in the detailed understanding of protein networks and supports the prediction of novel protein interactions and the reconstruction of protein complexes. Results: We introduce an integrative approach for predicting protein region interactions using a probabilistic model fitted to an observed protein network. In particular, we consider globular domains, short linear motifs and coiled-coil regions as potential protein-binding regions. Possible cooperations between multiple regions within the same protein are taken into account. A finegrained confidence system allows for varying the impact of specific protein interactions and region annotations on the modeling process. We apply our prediction approach to a large training set using a maximum likelihood method, compare different scoring functions for region interactions and validate the predicted interactions against a collection of experimentally observed interactions. In addition, we analyze prediction performance with respect to the inclusion of different region types, the incorporation of confidence values for training data and the utilization of predicted protein interactions. Contact: mario.albrecht@mpi-inf.mpg.de Supplementary information: Supplementary data are available at Bioinformatics online.

The foamy viral proteases (FV PRs) are set apart from other retroviral processing enzymes by unique features. The first remarkable property is that FV PRs are enzymatically active as high-molecular-mass Pro-Pol proteins. Hence there exist multiple forms of active FV PRs that likely contribute to cleavage site specificity. A FV PR of low molecular size is not detectable in purified virions, in contrast to PRs of other retroviruses that are found in virus particles. Because the major part of Pol remains attached to the amino-terminal enzymatically active PR protein region, the FV-specific way of expressing Pro-Pol polyproteins from a pol-specific transcript provides for the incorporation of Pro-Pol and IN into virus particles. Proteolytic processing of Gag and Pol proteins is incomplete and delayed. Another novel feature is that the catalytic center of the active dimers of cat FV PR consists of D-S/T-Q instead of D-S/T-G, an unprecedented feature of this enzyme. The temporal and spatial control and the factors that regulate FV PRs remain to be elucidated.

The epitopes recognized by 42 monoclonal antibodies directed against the human parainfluenza virus type 2 (hPIV-2) phosphoprotein (P) were mapped on the primary structure of the P protein by testing their reactivities with deletion mutants. By Western Immunoblotting with these monoclonal antibodies and P protein deletion mutants the region essential for P-P interactions was determined. The P protein region encompassing amino acids 211-248 was required for proper folding and oligomerization which is mediated by predicted coiled-coils in this region. The oligomer was shown to be a homotrimer by chemical cross-linking experiments.

Multiple-round in vitro transcription assays were performed using purified Escherichia coli RNA polymerase reconstituted with either wild-type or mutant final sigma70 proteins. These mutants, final sigma70(P504L) and final sigma70(S506F), bear single amino acid changes in conserved protein region 3. Behavior of the mutant enzymes on three test templates, bearing either the T7 A1, T5 N25, or T5 N25antiDSR promoter, were characterized. Transcription of all three promoter templates produced a pattern of specific abortive RNA species, which was qualitatively different for the mutants compared to the wild-type final sigma70 enzyme. Short abortive RNAs were produced at similar levels for mutant and wild-type enzymes. The production of longer abortive species was either reduced or increased by the mutant enzymes in a systematic manner that appears promoter-specific, and could be RNA length- or promoter distance-dependent. The process of abortive RNA transcription is thought to be tightly associated with that of promoter clearance. However, promoter clearance from these templates appears only slightly affected by the mutant enzymes. These mutants implicated region 3 of final sigma70 in the process of abortive transcription and suggest that the sequence of enzymatic events leading to the production of abortive or full-length RNA may be separable.

An evolutionary analysis of self peptides reported to be bound by HLA class I molecules showed that these peptides are largely derived from proteins that have been highly conserved in the history of mammals. These proteins also often have universal tissue expression and have a higher than average frequency of highly hydrophilic residues. The peptides themselves are generally still more highly conserved than the source proteins and have a higher frequency of highly hydrophobic residues, evidently often being derived from conserved hydrophobic cores of the source proteins. These results suggest that the mechanism by which peptides are derived for MHC presentation may preferentially select peptides from conserved protein regions. In the case of parasite-derived peptides, such a mechanism would be adaptive in that it would reduce the likelihood of escape mutants.

The wheat-grain proteome was investigated, as a basis for devising more efficient methods of cultivar identification or discrimination. Australian wheats (Halberd, Cranbrook, CD87 and Katepwa) were used as the basis of this study. These cultivars were selected on the basis of differences in the quality types represented, in terms of dough-processing attributes that can suit one cultivar better than another for specific types of industrial utilisation. Total wheat endosperm (flour) protein extracts were prepared from mature wheat for two-dimensional electrophoresis, across both acidic (pH 4-7) and basic (pH 6-11) pH ranges. Three particular regions of the proteome maps were chosen for close comparison, involving two sets of gluten proteins and a nongluten protein region (involving small heat shock proteins), based on previous protein characterisation. Differences in the nongluten protein regions (heat shock proteins and other unidentified polypeptides) are of particular interest as being possible targets for use in developing new approaches to cultivar discrimination, such as the development of simple immunoassays.

With the aid of gel filtration techniques (Sephadex G-200) the alkaline phosphatase (Bessey-Lowry-Brock) distribution patterns have been studied in the serum of control human subjects and of those with conditions known to affect total enzyme levels. Protein was scanned at 254 and 280 mμ and the 19S, 7S, and 4S peaks thus obtained were used as points of reference. The characteristic control serum revealed one sharp peak of enzyme activity in the 7S protein region. A similar but sharper peak was found in osteomalacia and Pagets' disease. In contrast, in malignant bone conditions 10.4%, in metastatic malignant liver disease 31.36% and in nonmalignant liver disease 12.7% of total enzyme moved with the 19S proteins. The patterns found in various conditions are reproducible, and that of metastatic malignant liver disease is particularly characteristic. The significance of the macromolecular-moving enzyme is discussed and is being investigated.

The cytoplasmic concentration of Z protein (Mr approximately 12,000) was significantly reduced in a series of implanted Morris hepatomas with varying degrees of differentiation. Approximately half of the [14C]palmitoyl-CoA added to cytosol fractions from control or host livers was bound to the Z protein region whereas a much smaller proportion was bound to this region in the cytosol of nine Morris hepatomas studied. The possible implications of these findings are discussed in relation to the abnormal regulation of lipid metabolism in hepatomas.

The interaction of prion protein (PrP) and α-synuclein (αSyn) oligomers causes synaptic impairment that might trigger Parkinson’s disease and other synucleinopathies. Here, we report that αSyn oligomers (αSynO) cluster with human PrP (huPrP) into micron-sized condensates. Multivalency of αSyn within oligomers is required for condensation, since clustering with huPrP is not observed for monomeric αSyn. The stoichiometry of the heteroassemblies is well defined with an αSyn:huPrP molar ratio of about 1:1. The αSynO−huPrP interaction is of high affinity, signified by slow dissociation. The huPrP region responsible for condensation of αSynO, residues 95−111 in the intrinsically disordered N-terminus, corresponds to the region required for αSynO-mediated cognitive impairment. HuPrP, moreover, achieves co-clustering of αSynO and Alzheimer’s disease-associated amyloid-β oligomers, providing a case of a cross-interaction of two amyloidogenic proteins through an interlinking intrinsically disordered protein region. The results suggest that αSynO-mediated condensation of huPrP is involved in the pathogenesis of synucleinopathies. Nadine S. Rosener et al. show that α-synuclein oligomers can cluster with human prion protein (huPrP) into condensates. The intrinsically disordered N-terminus of huPrP is necessary for this high-affinity interaction, suggesting a link between cluster formation and toxicity.