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Non-ribosomal peptide synthetases (NRPS) and polyketide synthases (PKS) found in bacteria, fungi and plants use two different types of thioesterases for the production of highly active biological compounds (1,2). Type [...]

A new and simpler method is devised for the direct and uniform metallization of DNA strands or its stretches, which makes use of the chemical reduction of the DNA-complexed salts and makes the manufacturing of DNA-based electronic devices more efficient. The method is based on the phenomenon of deposition of Ag(0) around aldehyde-modified DNA and hence also offers a possibility to exploit the arsenal of molecular biological tools in order to construct conductive DNA nanodevices.

The Bacillus subtilis Sfp protein activates the peptidyl carrier protein (PCP) domains of surfactin synthetase by transferring the 4′-phosphopantetheinyl moiety of coenzyme A (CoA) to a serine residue conserved in all PCPs. Its wide PCP substrate spectrum renders Sfp a biotechnologically valuable enzyme for use in combinatorial non-ribosomal peptide synthesis. The structure of the Sfp-CoA complex determined at 1.8 Å resolution reveals a novel α/β-fold exhibiting an unexpected intra-molecular 2-fold pseudosymmetry. This suggests a similar fold and dimerization mode for the homo-dimeric phosphopantetheinyl transferases such as acyl carrier protein synthase. The active site of Sfp accommodates a magnesium ion, which is complexed by the CoA pyrophosphate, the side chains of three acidic amino acids and one water molecule. CoA is bound in a fashion that differs in many aspects from all known CoA-protein complex structures. The structure reveals regions likely to be involved in the interaction with the PCP substrate. [ABSTRACT FROM AUTHOR]