Sequence and structural features of carbohydrate binding in proteins and assessment of predictability using a neural network

BACKGROUND: Protein-Carbohydrate interactions are crucial in many biological processes with implications to drug targeting and gene expression. Nature of protein-carbohydrate interactions may be studied at individual residue level by analyzing local sequence and structure environments in binding regions in comparison to non-binding regions, which provide an inherent control for such analyses. With an ultimate aim of predicting binding sites from sequence and structure, overall statistics of binding regions needs to be compiled. Sequence-based predictions of binding sites have been successfully applied to DNA-binding proteins in our earlier works. We aim to apply similar analysis to carbohydrate binding proteins. However, due to a relatively much smaller region of proteins taking part in such interactions, the methodology and results are significantly different. A comparison of protein-carbohydrate complexes has also been made with other protein-ligand complexes. RESULTS: We have compiled statistics of amino acid compositions in binding versus non-binding regions- general as well as in each different secondary structure conformation. Binding propensities of each of the 20 residue types and their structure features such as solvent accessibility, packing density and secondary structure have been calculated to assess their predisposition to carbohydrate interactions. Finally, evolutionary profiles of amino acid sequences have been used to predict binding sites using a neural network. Another set of neural networks was trained using information from single sequences and the prediction performance from the evolutionary profiles and single sequences were compared. Best of the neural network based prediction could achieve an 87% sensitivity of prediction at 23% specificity for all carbohydrate-binding sites, using evolutionary information. Single sequences gave 68% sensitivity and 55% specificity for the same data set. Sensitivity and specificity for a limited galactose binding data set were obtained as 63% and 79% respectively for evolutionary information and 62% and 68% sensitivity and specificity for single sequences. Propensity and other sequence and structural features of carbohydrate binding sites have also been compared with our similar extensive studies on DNA-binding proteins and also with protein-ligand complexes. CONCLUSION: Carbohydrates typically show a preference to bind aromatic residues and most prominently tryptophan. Higher exposed surface area of binding sites indicates a role of hydrophobic interactions. Neural networks give a moderate success of prediction, which is expected to improve when structures of more protein-carbohydrate complexes become available in future

Empowering Leadership and Team Creativity: An Examination of Direct and Indirect Path

In this research, we investigated how empowering leadership is related with team level creativity of employees. Integrating theory of group behavior with componential theory of creativity, we found that empowering leadership behavior affects the team level creativity of employees directly and indirectly through the mediation of team learning behavior and team psychological empowerment as team process and team emergent states. For this research we collected data from two sources (Subordinates, and Supervisors) by temporally dividing data collection process into two points in time for independent, dependent, and mediating variables from employees of a bank operating in Pakistan. Preliminary analysis and analysis with mediation and indirect affects performed to check the direct and indirect effects. Mplus 7.0 was used with random model techniques to analyze hypothesized model for employees’ sample (N = 343). Mediation was analyzed using indirect effect of random models and further confirmed the confidence using bootstrapping procedure. Further research findings, implications, and future research directions also discussed in this research. Keywords: Empowering leadership; Team learning behavior; Team psychological empowerment; Team creativit

How Are They Gaining such Positions? An Examination of Antecedents of Informal Leadership at Organizations

Drawing upon leadership emergence and conservation of resource theories, we proposed that relationship with formal leaders, voice behaviors of employees, and impression management tactics of employees influence the acquisition of informal leadership position in their social circles at organizations. We also found that education of focal employee also plays vital role in determining emergence of informal leadership in social circles. Research implications and future research directions also discussed. Keywords: LMX, empowering leadership, voice behavior, impression management, political skill

Gender Similarity and Individual Creativity as Moderators of the Relationship between Informal Leadership and Leader-Member-Exchange: A Longitudinal Study

This longitudinal study examines the quality relationship building between informal and formal leadership. Multisource data gathering technique was used to collect data from 46 teams with 333 subordinates and 46 supervisors at time 1 and 33 teams with 189 subordinates and 33 supervisors at time 2 of an Insurance company operating in Pakistan. Using threat theory we tested two contingencies: demographic similarity and competency on relationship building between informal and formal leadership. We found that Informal leadership position is positively related with Leader Member Exchange (LMX) quality and provided support to LMX literature that informal leadership precede LMX. We also found support for competency threat to shape relationship between informal leadership and LMX. Implications and future research directions also discussed. Keywords: Demographic Similarity, Education Similarity, Informal Leadership, Individual Creativity, Leader Member Exchange (LMX), Vertical Relations, Value Threat

Social Side of Creativity: Voice Behavior as Moderator of the Relationship between Individual Creativity and Leader-Member-Exchange

In this study we examined relationship between individual creativity of subordinates and Leader Member Exchange (LMX) at organizations. Using multisource data gathering technique we collected data from 40 teams with 293 employees working at different controlling offices of a private software house operates in Pakistan. We integrated creativity, trust and Leader Member Exchange (LMX) literature to understand social side of creativity at organizations. We found that individual creativity is positively related with Leader Member Exchange (LMX) and provided support to creativity literature that creativity as a unique resource of individuals is predictor of quality relationship with formal leaders at organizations. We also provided support to Leader Member Exchange (LMX) literature that individual creativity as a unique competency of subordinates precede Leader Member Exchange (LMX) at organizations. Using interpersonal trust literature we also tested two contingencies: challenging voice and supportive voice on relationship building between individual creativity and Leader Member Exchange (LMX) at organizations. We found that behaviors which promote interpersonal trust also strengthen the relationship between individual creativity and Leader Member Exchange (LMX) at organizations and behaviors which impede interpersonal trust also weaken the relationship between individual creativity and Leader Member Exchange (LMX) at organizations. Implications of the findings and future research directions also discussed. Keywords: Individual Creativity, Leader Member Exchange (LMX), Voice Behavior, Challenging Voice, Supportive Voice, Interpersonal Trust

Strategic Human Resource Management and Employee Creativity: The Role of Leadership Style and Knowledge Management Capacity

In this study we explored the relationship between strategic human resource management practices and creativity of the employees. Using multisource data gathering technique, we collected data from 382 employees and their respective 68 supervisors working at ministry of migration and displacement Baghdad-Iraq. We built on the theoretical framework based on employee–organizational relationship theories, specifically, organizational support theory, and leadership theory. We found that strategic human resource management practices affect the employees’ potential to produce creative ideas at organizations directly or indirectly through knowledge acquisition, knowledge sharing, and knowledge application. We also found that leadership styles affect the relationship between strategic human resource management practices and creativity of the employees. The results of this study provided new insight among strategic human resource management practice, knowledge management capacity, knowledge application, creativity of employees, transactional leadership, transformational leadership style, and the interaction of leadership styles with human resource management practices for creativity of employees. Research implications and future research directions are also discussed in this research. Keywords: Strategic human resource practices, knowledge management capacity, employee creativity, transactional leadership, transformational leadershi

Contribution à la multi-modélisation des applications distribuées pour le contrôle de l'évolution des logiciels

The software evolution control requires a complete understanding of the changes and their impact on the various systems artifacts. We propose a multi-modeling approach for the change impact analysis to provide assistance in understanding the effects of projected or actual changes in distributed software systems. This work elaborate the modeling of software artifacts along with their various interdependencies to build a knowledge-based system, which allows, among others, an assistance for the software developers or maintenance engineers to establish an a priori evaluation of impact of changes. The model we develop integrates two major descriptions of software, at first, the underlying structural description that encompasses the levels of granularity and abstraction of software artifacts, and then the qualitative description designed to integrate the structural description. Initially, the formal models are designed separately for the respective descriptions, and then these are integrated for the objective to study the change impact and its potential propagation through the affected software artifacts. For a change, it is important to establish a qualitative assessment of its impact. The integrated modeling leads to a reasoning based on expert rules. The proposed model is being tested and validated through the development of a platform, implemented in the Eclipse environment.Le contrôle de l'évolution des logiciels exige une compréhension profonde des changements et leur impact sur les différents artefacts du système. Nous proposons une approche de multi-modélisation pour l'analyse d'impact du changement pour une compréhension des effets des modifications prévus ou réels dans les systèmes distribués. Ce travail consiste à élaborer une modélisation des artefacts logiciels et de leur différents liens d'interdépendance pour construire un système à base de connaissance permettant, entre autres, d'assister les développeurs et les chargés de l'évolution des logiciels pour étblir une évaluation a priori de l'impact des modifications.La modélisation que nous élaborons intègre deux descriptions majeures des logiciels, dans un premier temps, la description structurelle sous-jacente qui englobe l'ensemble des niveaux granulaires et l'abstraction des constituants logiciels, et ensuite la description qualitative conçue pour s'intégrer à la description précédente. Deux modèles, d'abord élaborés individuellement pour les deux descriptions respectives, ont été intégrés ou mis en correspondance dans l'objectif d'étudier l'impact de toute modification et sa potentielle propagation à travers les constituants logiciels concernés. Lors de chaque modification, il devient alors possible d'établir un bilan qualitatif de son impact. La modélisation intégrée est élaborée pour se prêter à un raisonnement à base de règles expertes. La modélisation proposée est en cours d'expérimentation et validation à travers le développement d'une plate-forme d'implémentation basée sur l'environnement Eclipse