Antibiotic abundance: Several new uridyl peptide antibiotics were identified from a heterologous producer strain containing the mureidomycin/napsamycin biosynthetic gene cluster by using HRMS and LC-ESI-MS/MS. Analysis of the new compounds and the corresponding gene cluster revealed NpsB, an N-acetyltransferase, to be responsible for acetylation of the uridyl peptide antibiotic. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.