Many mitochondrial proteins are synthesized with N-terminal presequences that are removed by specific peptidases. The N-termini of the mature proteins and thus peptidase cleavage sites have only been determined for a small fraction of mitochondrial proteins and yielded a controversial situation for the cleavage site specificity of the major mitochondrial processing peptidase (MPP). We report a ...

FENs (flap endonucleases) and related FEN-like enzymes [EXO-1 (exonuclease-1), GEN-1 (gap endonuclease 1) and XPG (xeroderma pigmentosum complementation group G)] are a family of bivalent-metal-ion-dependent nucleases that catalyse structure-specific hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair and recombination. In the case of FENs, the ability to ...

The Trp-cage, at 20 residues in length, is generally acknowledged as the smallest fully protein-like folding motif. Linking the termini by a two-residue unit and excising one residue affords circularly permuted sequences that adopt the same structure. This represents the first successful circular permutation of any fold of less than 50-residue length. As was observed for the original topology, ...

The aggresome pathway is activated when proteasomal clearance of misfolded proteins is hindered. Misfolded polyubiquitinated protein aggregates are recruited and transported to the aggresome via the microtubule network by a protein complex consisting of histone deacetylase 6 (HDAC6) and the dynein motor complex. The current model suggests that HDAC6 recognizes protein aggregates by binding dire...

Polynucleotide kinase/phosphatase (PNKP) is a critical mammalian DNA repair enzyme that generates 5'-phosphate and 3'-hydroxyl groups at damaged DNA termini that are required for subsequent processing by DNA ligases and polymerases. The PNKP phosphatase domain recognizes 3'-phosphate termini within DNA nicks, gaps, or at double- or single-strand breaks. Here we present a mechanistic rationale f...

Intonacija, akcentuacija sono termini ricorrenti nei testi di Michail Bachtin e Valentin N. Vološinov. Ogni enunciazione, ogni testo, ha la sua intonazione specifica accentuazione. La comprensione non è solo del contenuto, significato, ma anche soprattutto testo senso, il senso dato proprio dalla particolare, intonazione, singolare Ciò vale soltanto nel parlato, nella scrittura, dunque lettura ...

In the title compound, C10H19N3O4, the N- and C-termini are protonated and ionized, respectively, and the mol-ecule forms a zwitterion. The main chain is in a folded form. In the crystal, the N-terminal -NH3 (+) group hydrogen bonds to three C-terminal -COO groups and one carbonyl O atom, forming a three-dimensional network. In addition, an N-H⋯O hydrogen bond between the amide groups of the mi...

Serotonin-bonded silica was developed for specific extraction of sialic-acid-containing glycans and glycopeptides. Serotonin, coupled by reductive amination with aldehyde silica particles via its ethylamino group, has strong affinity to sialic acid in glycan chain termini. Sialylated glycans trapped on serotonin silica particles are released by washing with ammonium acetate solution, providing ...

Alternative transposition can induce genome rearrangements, including deletions, inverted duplications, inversions, and translocations. To investigate the types and frequency of the rearrangements elicited by a pair of reversed Ac/Ds termini, we isolated and analyzed 100 new mutant alleles derived from two parental alleles that both contain an intact Ac and a fractured Ac (fAc) structure at the...