Shigella is one of the most common bacterial pathogens that are isolated from patients with diarrhea. Various attempts are being made worldwide with encouraging observations; still the emergence of multidrug-resistant Shigella strains and a continuous high disease incidence imply that shigellosis is an unsolved global health problem which can probably be solved only by developing a proper vaccine and a vaccine regime for the disease. The need of the hour is to foster the development of an effective vaccine which should not only serve to improve hygiene but also should be able to curb infections by the pathogen. This goal can only be achieved by gaining proper detailed knowledge underlying Shigella pathogenesis. The analyses of the Shigella invasion proteins which have been long been targeted to be potential candidate vaccines remains an open ended problem and forms the core of this present computational study which identifies the fact that long regions in the structure of the proteins are disordered having no distinct structural conformation; multiple alignments however, did not show any conserved stretches in the disordered regions. The results probably explain the ability of these proteins to interact with multiple cellular proteins and perform a diverse array of functions leading to successful pathogenesis.
Two-dimensional electrophoresis (2-D PAGE) led to identification in the polypeptide maps of boar seminal plasma of four conserved polypeptides with identical molecular weight of 24 kDA, and different ranges of isoelectric point (pI): (1) 7.4-7.7, (2) 8.1-8.4, (3) 8.5-8.8 and (4) 9.2-9.4. In the current study the molecular structures of these polypeptides were analysed, for the first time, by mass spectrometry (LC – MS/MS). Computerized mass spectrometry analysis of the peptides obtained after trypsin-digestion of the polypeptides demonstrated their similarity to the family of spermadhesins (crystal structure of two members of the spermadhesin family), especially to epididymal spermadhesin AWN-1. In addition, homology was found of peptides 3 and 4 with a lysozyme C precursor (1,4-beta-N-acetylmuramidase C). The results presented might indicate the participation of the analysed polypeptides in the processes accompanying fertilization.
This paper examines the short- and long- term effects of increasing minimum wage rates for farm workers in South Africa on structural unemployment and rising food prices in the economy. The Pearson correlation model was used to establish association between variables. Analysis found a negative association (–0.651) between wage rate and employment of farm workers, while a positive (0.021) association was found to exist between wage rate (W) increases and food prices (Fp). No association (0.001) was found between employment and food prices (Fp). Co-integration was further employed to determine the short-term and long-term relationships, and the analysis found wages to have a positive and significant (0.453) effect on structural unemployment of farm workers. Unemployment was observed to be wage elastic in the long term and wage inelastic in the short term. The long-term relationship showed increasing unemployment in agriculture (L) and rising food prices (Fp) (1.168), while the short-term relationship showed a signifi cant error correction coeffi cient (ECT) with an expected starting point of 41.9% adjustment rate towards long-term equilibrium within a year. Structural analysis confi rmed an inelastic demand for basic food. The study suggest government subsidies to farmers through cost-cutting technologies and farm worker’s skills development on the use of these technologies.
Two early nodulin 40 (enod40) genes, ENOD40-1, the shortest legume ENOD40 gene, and ENOD40-2, were isolated from Lupinus luteus, a legume with indeterminate nodules. Both genes were expressed at similar levels during symbiosis with nitrogen-fixing bacteria. ENOD40 phylogeny clustered the L. luteus genes with legumes forming determinate nodules and revealed peptide similarities. The ENOD40-1 small ORF A fused to a reporter gene was efficiently expressed in plant cells, indicating that the start codon is recognized for translation. The ENOD40-1 RNA structure predicted based on Pb(II)-induced cleavage and modeling revealed four structurally conserved domains, an absence of domain 4 characteristic for legumes of indeterminate nodules, and interactions between the conserved region I and a region located upstream of domain 6. Domain 2 contains Mg(II) ion binding sites essential for organizing RNA secondary structure. The differences between L. luteus and Glycine max ENOD40 RNA models suggest the possibility of a switch between two structural states of ENOD40 transcript.
RNA silencing is one of the important phenomenon in plant defense mechanism, it actively protect host plants against viral infections. Existing viruses must have developed counter defense strategies to survive this arms race. Such counter defense strategy is the viral silencing suppressor (VSRs) which have been reported to directly interfere with the various steps leading to the interference of viral RNAs. Most identified VSRs are multifunctional, besides being RNA-silencing suppressors, they often perform essential roles by functioning as coat proteins, helper components for viral transmission, replicases and movement proteins, proteases or transcriptional regulators. One such identified VSR is AC4 of Sri Lankan cassava mosaic virus strain. Trivial knowledge about the structure –function relationship of this VSR leads to this work, where we focus on the structure generation by modelling to identify the mode of interactions with the various effector molecules of the silencing pathways. Structural analyses have been performed to screen interacting residues. Results indicate conserved structural features which signify propensity of functional interactions and further shows that this VSR can be a potent tool for the analysis of RNA silencing mechanisms and the relationships between different silencing pathways and VSRs.