Microbial cleavage of dimethylsulfoniopropionate (DMSP) producing dimethyl sulfide (DMS) and acrylate is an important step in global sulfur cycling. Acrylate is toxic for cells, and thus should be metabolized effectively for detoxification. There are two proposed pathways for acrylate metabolism in DMSP-catabolizing bacteria, the AcuN-AcuK pathway and the PrpE-AcuI pathway. AcuH is an acryloyl-...

Kinase homology domain (KHD) phosphorylation is required for activation of guanylyl cyclase (GC)-A and -B. Phosphopeptide mapping identified multiple phosphorylation sites in GC-A and GC-B, but these approaches have difficulty identifying sites in poorly detected peptides. Here, a functional screen was conducted to identify novel sites. Conserved serines or threonines in the KHDs of phosphoryla...

Allelic imbalance of thymidylate synthase (TYMS) is attributed to polymorphisms in the 5'- and 3'-untranslated region (UTR). These polymorphisms have been related to the risk of suffering different cancers, for example leukemia, breast or gastric cancer, and response to different drugs, among which are methotrexate glutamates, stavudine, and specifically 5-fluorouracil (5-FU), as TYMS is its di...

The catalytically essential glutamate residue that initiates catalysis by abstracting the substrate alpha-hydrogen as H+ is located at position 376 (mature MCADH numbering) on loop JK in medium chain acyl-CoA dehydrogenase (MCADH). In long chain acyl-CoA dehydrogenase (LCADH) and isovaleryl-CoA dehydrogenase (IVDH), the corresponding Glu carrying out the same function is placed at position 255 ...

Here we present the cloning, expression and immunocytochemical localization of a novel 24 kDa protein, designated spinalin, which is present in the spines and operculum of Hydra nematocysts. Spinalin cDNA clones were identified by in situ hybridization to differentiating nematocytes. Sequencing of a full-length clone revealed the presence of an N-terminal signal peptide, suggesting that the mat...

The gene encoding hydroxyisourate hydrolase, a novel ureide-metabolizing enzyme, has been cloned from soybean (Glycine max). The gene encodes a protein that is 560 amino acids in length and contains a 31-amino acid signal sequence at the N terminus that is not present in the mature protein. The presence of two SKL motifs near the C terminus suggests that the protein resides in the peroxisome. T...

PURPOSE The COOH-terminal extension segment of alphaB-crystallin, a member of small heat shock protein (sHSP) family, appears to be a flexible polypeptide segment susceptible to proteolytic truncation and modifications under physiological conditions. To investigate its role on the structure and chaperone-like activity, we constructed various mutants of porcine alphaB-crystallin with either COOH...

Bordetella adenylate cyclase toxin-hemolysin (CyaA, AC-Hly, or ACT) permeabilizes cell membranes by forming small cation-selective (hemolytic) pores and subverts cellular signaling by delivering into host cells an adenylate cyclase (AC) enzyme that converts ATP to cAMP. Both AC delivery and pore formation were previously shown to involve a predicted amphipathic alpha-helix(502-522) containing a...

Most of the studies about NH4+ stress mechanism simply address the effects of free NH4+, failing to recognize the changed nitrogen assimilation products. The objective of this study was to elucidate the effects of glutamate on root growth under high ammonium (NH4+) conditions in winter wheat (Triticum aestivum L.). Hydroponic experiments were conducted using two wheat cultivars, AK58 (NH4+-sens...

Proteomics researchers are constantly on the lookout for new and better ways to fractionate their samples since the mind-numbing complexity of virtually any proteome easily defeats the ability of even the most advanced mass spectrometers or other instruments to “see” all of the molecules in the sample. In this issue of Nature Chemical Biology, Weerapana et al. report new chemical tools for this...