Inspired by the broad substrate scope of TmTK, we studied the enzymes involved in nucleotide synthesis in the hyperthermostable bacterium T. maritima with the aim of identifying additional wide spectrum enzymes for biocatalytic applications. In total, 13 enzymes of T. maritima were expressed, purified and characterized. The substrate scope of active enzymes was analyzed using a set of 26 natural (deoxy)nucleosides or nucleotides as substrates. Finally, we demonstrated the synthesis of base-and sugar-modified nucleotides in cascade reactions with T. maritima NMPKs. Thus, this study presents a set of thermostable TmNMPKs suitable for the synthesis of natural and modified nucleotides.