Cloning and expression of synthetic genes encoding angiotensin-I converting enzyme (ACE)-inhibitory bioactive peptides in Bifidobacterium pseudocatenulatum.

A wide range of biopeptides potentially able to lower blood pressure through inhibition of the angiotensin-I converting enzyme (ACE) is produced in fermented foods by proteolytic starter cultures. This work applies a procedure based on recombinant DNA technologies for the synthesis and expression of three ACE-inhibitory peptides using a probiotic cell factory. ACE-inhibitory genes and their pro-active precursors were designed, synthesized by PCR, and cloned in Escherichia coli; after which, they were cloned into the pAM1 E.

Genome walking by Klenow polymerase.

Genome walking procedures are all based on a final polymerase chain reaction amplification, regardless of the strategy employed for the synthesis of the substrate molecule. Here we report a modification of an already established genome walking strategy in which a single-strand DNA substrate is obtained by primer extension driven by Klenow polymerase and which results suitable for the direct sequencing of complex eukaryotic genomes. The efficacy of the method is demonstrated by the identification of nucleotide sequences in the case of two gene families (chiA and P1) in the genomes of several maize species.

Genome walking in eukaryotes.

Genome walking is a molecular procedure for the direct identification of nucleotide sequences from purified genomes. The only requirement is the availability of a known nucleotide sequence from which to start. Several genome walking methods have been developed in the last 20 years, with continuous improvements added to the first basic strategies, including the recent coupling with next generation sequencing technologies.

The photosynthetic membrane proteome of Rhodobacter sphaeroides R-26.1 exposed to cobalt.

Cells of the carotenoidless strain R-26.1 of Rhodobacter sphaeroides were grown in the presence of a high concentration (5 mM) of cobalt ions. The photosynthetic intracytoplasmic membranes were isolated and investigated by proteomic analysis using non-denaturating blue native electrophoresis in combination with LC-ESI-MS/MS.