2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/159715Given an ultragraph in the sense of Tomforde, we construct a topological quiver in the sense of Muhly and Tomforde in such a way that the universal C*-algebras associated to the two objects coincide. We apply results of Muhly and Tomforde for topological quiver algebras and of Katsura for topological graph C*-algebras to study the K-theory and gauge-invariant ideal structure of ultragraph C*-algebras.20 pages, Version 2 Comments: final version to appear in Studia MathOperator Algebras46L05text