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Analysis of affinity‐purified preparations of the fetuin‐binding proteins from elderberry bark and fruits revealed besides the previously reported Neu5Ac(α‐2,6)Gal/GalNAc‐specific type 2 ribosome‐inactivating proteins (RIP) the occurrence of single chain proteins of 22 kDa, which according to their N‐terminal amino acid sequence correspond to the second part of the B chain of the respective type 2 RIP. Both proteins are very similar except that the polypeptides of the fruit lectin are 10 amino acid residues longer than these from the bark lectin. Our findings not only demonstrate the occurrence of carbohydrate‐binding fragments of type 2 RIP but also provide further evidence that type 2 RIP genes give rise to complex mixtures of type 2 RIP/lectins in elderberry.

Leukotriene A4hydrolase is a cytosolic metalloenzyme of the arachidonic acid biosynthetic pathway responsible for leukotriene A4conversion into leukotriene B4. In addition to its epoxide hydrolase properties, this enzyme exhibits an aminopeptidase activity which was used as an assay to monitor the purification of a novel form of leukotriene A4hydrolase from Xenopus laevisskin exudate. This 70 kDa, secreted, form of leukotriene A4hydrolase was identified by immunochemical cross‐reactivity with anti‐human leukotriene A4hydrolase antibodies and by its capacity to convert leukotriene A4into leukotriene B4. Moreover this enzyme produced a second metabolite which could be the leukotriene B4isomer 5S,12R‐dihydroxy‐6,10‐trans‐8,14‐cis‐eicosatetraenoic acid, previously shown by Strömberg et al. (Eur. J. Biochem. 238 (1996) 599–605) to be formed by incubation of the leukotriene A4with amphibian tissue extracts. Partial amino acid sequencing of peptides generated by endolysin C fragmentation of the purified enzyme confirmed the presence, in X. laevisskin secretions, of a related but distinct form of leukotriene A4hydrolase which is likely to be responsible for the production of these eicosanoid metabolites of leukotriene A4.

A complete malolactic fermentation was achieved using Saccharomyces cerevisiaestrains coexpressing the genes mleSand mae1coding for the Lactococcus lactismalolactic enzyme and the Schizosaccharomyces pombemalate permease under the control of yeast promoters. The expression level of mae1greatly influences the kinetics of the reaction by controlling the rate of malate uptake meanwhile a high expression level of mleSinduces a partial consumption of malate derived from glucose by the malolactic enzyme. A strain expressing several copies of mae1and one copy of mleSdegrades 3 g/l of malate almost exclusively through the malolactic pathway in 4 days under enological conditions, without metabolic side effects.

The in vivo incorporation of [3H]phenylalanine into an apparent 15 kDa prosomatostatin was observed in the hypothalamus of rats injected with the labeled amino acid in the third ventricle. Precursor‐product relationships were established between this newly synthesized material and both somatostatin‐28 and ‐14.

cDNA clones encoding the mitogenic mannose/mal-tose-specific lectin from the rhizomes of hedge bindweed ( Calystegia sepium) have been isolated and sequenced. Comparison of the deduced amino acid sequence and the molecular weight of the lectin subunit as determined by mass spectrometry indicated that the mature protein comprises the entire open reading frame of the cDNA, which implies that the primary translation product contains no signal peptide and is not proteolytically processed. Searches in the databases revealed sequence homology with the previously described lectins from the taxonomically unrelated Moraceae species Artocarpus integrifoliaand Maclura pomifera.

Many lactic acid bacteria can carry out malolactic fermentation. This secondary fermentation is mediated by the NAD‐ and Mn2+‐dependent malolactic enzyme, which catalyses the decarboxylation of l‐malate to l‐lactate. The gene we call mleS, coding for malolactic enzyme, was isolated from Lactococcuslactis. The mleSgene consists of one open reading frame capable of coding for a protein with a calculated molecular mass of 59 kDa. The amino acid sequence of the predicted MleS gene product is homologous to the sequences of different malic enzymes. Bacterial and yeast cells expressing the malolactic gene convert l‐malate to l‐lactate.