VIPoma with expression of both VIP and VPAC1 receptors in a patient with WDHA syndrome.

We report a case of VIPoma in a 72-year-old female patient who presented with excessive diarrhea, severe hypokalemia, and acidemia. She had been referred to our hospital three times because of severe diarrhea. No primary tumor site was found by conventional techniques, including contrast-enhanced CT and MRI, angiography, endoscopy, and positron emission tomography (PET), but a tumor was subsequently found in the head of the pancreas by octreotide scanning.

Identification and transcriptional organization of a gene cluster involved in biosynthesis and transport of acinetobactin, a siderophore produced by Acinetobacter baumannii ATCC 19606T.

In order to assimilate iron, Acinetobacter baumannii ATCC 19606(T) produces a siderophore named acinetobactin (Ab) that is composed of equimolar quantities of 2,3-dihydroxybenzoic acid (DHBA), L-threonine and N-hydroxyhistamine. Application of the Fur titration assay system to A. baumannii genomic libraries, followed by further cloning of the regions surrounding the candidate genes, led to the identification of the Ab cluster, which harbours the genetic determinants necessary for the biosynthesis and transport of the siderophore.