M. BAKLI 1,2, Noureddine BOURAS 3,4, R. PAŞCALĂU 5, Laura ȘMULEAC 5 1 Département de Biologie, Faculté des Sciences et Technologie, Université de Aïn Temouchent, B.P 284, 46000, Aïn Temouchent, Algeria. 2 Physiologie, Physiopathologie et Biochimie de la Nutrition, Université de Tlemcen, Tlemcen, Algeria. 3 Département de Biologie, Faculté des Sciences de la Nature et de la Vie et Sciences de la Terre, Université de Ghardaïa, Ghardaïa, Algeria. 4 Laboratoire de Biologie des Systèmes Microbiens (LBSM), Ecole Normale Supérieure de Kouba, Alger, Algeria. 5 Banat’s University of Agriculture Science and Veterinary Medicine “King Michael I of Romania”, Faculty of Agriculture, 119 Calea Aradului, 300645, Timisoara, Romania. mahfoud.bakli@gmail.com
Xylanases (EC 3.2.1.x) are a widespread group of hydrolytic enzymes involved in xylan depolymerization. Xylan, the second most abundant polysaccharide in nature, is the major hemicellulosic constituent of the plant cell wall. To date, due to their eco-friendly nature xylanase, individually or in combination with other enzymes, have a widespread uses in various sectors of industries and agri-food processes. Xylanases are mainly produced by several microorganisms including bacteria, micro-fungi, algae, and some yeast. However, bacterial xylanases have been shown to possess an easy downstream process of industrial production with high production rate, and to ensure a more cost-effective process. Despite several reports investigating characterization, production, optimization, and isolation of xylanases from different Pseudomonas species, a study on the xylanase of the P. putida is still lacking. Recently, P. putida has emerged as a promising bacterial host for industry and plant biomass valorization due to its remarkably versatile metabolism, unique capacity to adapt to harsh environmental conditions, and to resist to difficult redox reactions, industrial solvents, and oxidative stresses. The aim of this study was to characterize xylanase from P. putida using bioinformatics analyses and homology modeling method. The secondary structural features of the protein was calculated by both PSIPRED and SOPMA tools which revealed that xylanase protein is composed of α-helix (41.74%), random coils (34.86 %), extended strand (16.60 %), and β-turn (7.80 %). The three-dimensional structure of xylanase protein model was predicted by homology modeling through the Phyre2 server. The structural refinement of this builded model was generated using Modrefiner and validated through the Ramachandran plot as obtained using the PROCHECK tool. Ligand binding site prediction by COFACTOR server was confident with a BS-score > 0.5. Protein-protein interaction networks demonstrated that xylanase had ten potential interacting partners with a high confidence score. The outcome of this in silico analysis could help for detection and characterization of such enzyme allowing its wide production and exploiting in various industrial and agri-food sectors.
Xylanase, Pseudomonas putida, in silico analysis, homology modeling.
Presentation: poster