Purification and characterization of a hygromycin B phosphotransferase from Streptomyces hygroscopicus

4 pages, 4 figures, 1 table, 20 references.A hygromycin B phosphotransferase activity from Streptomyces hygroscopicus has been highly purified by ammonium sulphate fractionation followed by affinity column chromatography through Sepharose-6B- hygromycin-B.The combined active fractions showed a singleprotein band (41 kDa) when subjected to polyacryl- amide gel electrophoresis in the presence of sodium dodecyl sulphate. When gel electrophoresis was performed under non-denaturing conditions, the single protein band promoted in situ phosphorylation of hygromycin B, indicating that this protein corresponded to the purified hygromycin B phosphotransferase. The enzyme has been purified 236-fold and approximate Km values of 0.56 pM and 36.4 pM for hygromycin B and ATP, respectively, were deduced.This research was supported by grants from the Comisión Asesora de Investigación Científica y Técnica (6131165 and 497) and by an institutional grant from the Fondo de Investigaciones Sanitarias to the Centro de Biología Molecular. M. Zalacaín holds a fellowship from the Consejo Superior de Investigaciones Científicas.Peer reviewe

La construcción de una elite urbana en una sociedad de nueva colonización: Tenerife

The conquest of the Canary Islands opens a new scenario for Castile at the end of the 15th C: if until then the territorial expansion was developed thanks to the Islamic enemy then, the Islands constitute a different area because of new factors -presented here- which made a new society governed by new matrices. The process is analyzed from the perspective of the constitution of the first oligarchy in the island.La conquista de Canarias abre un escenario inédito a Castilla a finales del s. XV: si hasta entonces laexpansión territorial se desarrolló a costa del enemigo islámico, las islas serán un espacio distinto por diversosfactores —aquí expuestos— que hicieron que la nueva sociedad se rigiera por nuevas matrices. Se analiza elproceso desde el punto de vista de la constitución de la primera oligarquía de la isla