IAL   21557
INSTITUTO DE AGROBIOTECNOLOGIA DEL LITORAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Analysis of sugar partitioning in actinobacteria: studies of duplicated genes in Rhodococcus josti
Autor/es:
IGLESIAS AA; ASENCION DIEZ MD; CEREIJO AE
Lugar:
Buenos Aires
Reunión:
Congreso; Joint Meeting of Bioscience Societies - LIII Argentine Society for Biochemical and Molecular Biology Research (SAIB) Annual meeting; 2017
Resumen:
ANALYSIS OF SUGAR PARTITIONING IN ACTINOBACTERIA:STUDIES OF DUPLICATED GENES INRhodococcus jostiiAntonela E Cereijo, Matías Damián Asencion Diez, AlbertoA IglesiasInstituto de Agrobiotecnología del Litoral (CONICET-UNL)The study of enzymes determining the use of glucose-1P (Glc-1P)for the production of different carbohydrates is critical for a better understandingof developmental biology, physiology, and metabolismof biotechnological microorganisms, such as Rhodococcus jostii andStreptomyces coelicolor. The genome from R. jostii, an oleaginousbacteria belonging to actinobacteria, shows many gene duplicationsuch as those coding for UDP-glucose pyrophosphorylase (GalU),glycogen synthase or trehalose-6P synthase. Albeit the organismpresents single gene coding for ADPglucose pyrophosphorylaseand the bifunctional protein GlmU. We performed the molecularcloning of R. jostii galU1 and galU2 genes respectively encodingthe enzymes RjoGalU1 and 2, which share more than 78% identity.Also, in preliminary structural analysis RjoGalU2 behaved asa trimer, differing from other prokaryotic GalUs. After recombinantexpression and purification, the comparative kinetic characterizationshowed that RjoGalU2 has 25-fold more activity than RjoGalU1 regardingUDP-Glc synthesis; although both enzymes depicted S0.5values for both substrates (UTP and Glc-1P) in the same order ofmagnitude. Both GalUs from R. jostii showed a high degree of promiscuitytowards sugar-1Ps. Remarkably, RjoGalU2 depicted oneorder of magnitude higher activity with glucosamine-1P (GlcN-1P)than with Glc-1P, thus suggesting this enzyme should be reannotatedaccording to its principal activity rather than GalU. Sugar-1P issubstrate of the NDPsugar pyrophosphorylases that produces differentNDP-sugar, which are used by different enzymes (i.e., glycosyltransferases) leading the monosaccharide to carbohydrates multifacetedroutes. In this regard, our results reinforce the importanceof deepen the structure to function analysis of carbohydrate relatedenzymes from bacteria to further understand evolutive mechanisms,physiological behaviors and even identify tools for future biotechnologicalapplications.