Class IV mammalian alcohol dehydrogenase Structural data of the rat stomach enzyme reveal a new class well separated from those already characterized

AbstractThe stomach form of alcohol dehydrogenase has been structurally evaluated by peptide analysis covering six separate regions of the rat enzyme. Overall, this new structure diners widely (32–40% residue differences) from the structures of three classes of alcohol dehydrogenase characterized before from the same species. Consequently, this novel enzyme constitutes a true fourth class of mammalian alcohol dehydrogenase. In particular, differences are extensive also towards class II, although enzymatic and physicochemical properties initially suggested overall similarities with class II. The new structure establishes the presence of one further alcohol dehydrogenase mammalian gene, extends the enzyme family derived from repeated gene duplications, and confirms tissue-specific expressions

International online education: the S-Star trial bioinformatics course

Six universities from five continents collaborated to provide the S-Star Trial Bioinformatics Online course (http://www.s-star.org/). The course is a global experiment in Bioinformatics Distance Education. The S* Life Science Informatics Alliance is the result of cooperation between Karolinska Institutet Sweden, the National University of Singapore, Stanford University USA, Uppsala University Sweden, The University of Sydney Australia, and the University of Western Cape South Africa. The S-Star group will be joined by the University of California San Diego, through the San Diego Supercomputer Center. Teaching cooperation was initiated because there is an overall global demand for bioinformatics education. The S-Star alliance provides a global, unified bioinformatics learning environment made up of modular courses in the disciplines of genomics, bioinformatics, and medical informatics. The initial aims of the group are to collaboratively provide: (1) a globally accessible online course for training in bioinformatics and genomics; (2) accessibility to the highest possible quality of online courseware available in the world today; (3) high quality assessment, grading and courseware that has been approved by the educators from the host institutions; and (4) an integrated modular learning environment that allows a student to select from both prerequisite modules and advanced modules in order to build a comprehensive program in genomics and bioinformatics. The main mission of S-Star is to provide an introductory course in bioinformatics to anyone with Internet access. Classes are given in English, regardless of whether the classes are attended by individuals or in groups

Computational studies of human class V alcohol dehydrogenase - the odd sibling

Background: All known attempts to isolate and characterize mammalian class V alcohol dehydrogenase (class V ADH), a member of the large ADH protein family, at the protein level have failed. This indicates that the class V ADH protein is not stable in a non-cellular environment, which is in contrast to all other human ADH enzymes. In this report we present evidence, supported with results from computational analyses performed in combination with earlier in vitro studies, why this ADH behaves in an atypical way. Results: Using a combination of structural calculations and sequence analyses, we were able to identify local structural differences between human class V ADH and other human ADHs, including an elongated beta-strands and a labile a-helix at the subunit interface region of each chain that probably disturb it. Several amino acid residues are strictly conserved in class I-IV, but altered in class V ADH. This includes a for class V ADH unique and conserved Lys51, a position directly involved in the catalytic mechanism in other ADHs, and nine other class V ADH-specific residues. Conclusions: In this study we show that there are pronounced structural changes in class V ADH as compared to other ADH enzymes. Furthermore, there is an evolutionary pressure among the mammalian class V ADHs, which for most proteins indicate that they fulfill a physiological function. We assume that class V ADH is expressed, but unable to form active dimers in a non-cellular environment, and is an atypical mammalian ADH. This is compatible with previous experimental characterization and present structural modelling. It can be considered the odd sibling of the ADH protein family and so far seems to be a pseudoenzyme with another hitherto unknown physiological function

Additional file 1: Table S1. of Computational studies of human class V alcohol dehydrogenase - the odd sibling

Nomenclature for Human Alcohol Dehydrogenase. (PDF 36 kb