Abstract Catalytic triads, composed of a serine or cysteine nucleophile, histidine, and third triad residue (typically Asp/Glu/Asn), are common in enzyme active sites catalyze wide variety chemical reactions. Two types triads can be distinguished: We refer to them as Nδ‐ Nϵ‐configured, depending on whether the histidine imidazole Nδ Nϵ atom is close nucleophile Oγ/Sγ. In this study, we have ana...

Histidine triad nucleotide-binding 2 (HINT2), a member of the histidine triad proteins family, sensitizes cells to apoptosis in hepatocellular carcinoma. Here, we showed that HINT2 expression is lower in primary colorectal cancer (CRC) and metastasis tissues than in normal colorectal tissues, and that HINT2 abundance is inversely correlated with CRC tumor stage. Treating CRC cells with 5-aza-2'...

Outer membrane phospholipase A (OMPLA) from Escherichia coli is an integral-membrane enzyme with a unique His-Ser-Asn catalytic triad. In serine proteases and serine esterases usually an Asp occurs in the catalytic triad; its role has been the subject of much debate. Here the role of the uncharged asparagine in the active site of OMPLA is investigated by structural characterization of the Asn15...

MbeA is a 60 kDa protein encoded by plasmid ColE1. It plays a key role in conjugative mobilization. MbeA*, a slightly truncated version of MbeA, was purified for in vitro analysis. MbeA* catalysed DNA cleavage and strand-transfer reactions using oligonucleotides embracing the ColE1 nic site, which was mapped to 5'-(1469)CTGG/CTTA(1462)-3'. Thus MbeA is the relaxase for ColE1 conjugal mobilizati...

Histidine 57 of the catalytic triad of trypsin was replaced with alanine to determine whether the resulting variant would be capable of substrate-assisted catalysis [Carter, P., & Wells, J. A. (1987) Science 237, 394-9]. A 2.5-fold increase in kcat/Km was observed on tri- or tetrapeptide substrates containing p-nitroanilide leaving groups and histidine at P2. In contrast, hydrolysis of peptide ...

We studied the effects of fragile histidine triad (FHIT) gene overexpression mediated by an adenoviral vector, Ad-FHIT, on cell proliferation, apoptosis, and cell cycle kinetics in human cancer cells and on tumorigenicity and tumor growth in nude mice. Overexpression of the FHIT gene significantly inhibited cell growth in various Ad-FHIT-transduced human lung cancer cells and head and neck carc...

Loss of expression of the Fhit protein is often associated with the development of many human epithelial cancers, including lung and cervical carcinomas. Restoration of Fhit expression in cell lines derived from these tumors has however yielded conflicting results, prompting the need for careful evaluation of the oncosuppressive potential of FHIT. In the present study, we have investigated the ...