PolyG sequences

Only the S-enantiomer, the teratogenic form, fits properly into the major groove of the double helix and binds to the polyG sequences. It seems that a very specific stereochemical interaction may be necessary for this toxic effect to occur. 

A generic source-based name of a polymer has two components in the following sequence (1) a polymer class (generic) name (polyG) followed by a colon and (2) the actual or hypothetical monomer name(s) (A, B, etc...), always parenthesized in the case of a copolymer. In the case of a homopolymer parentheses are introduced when it is necessary to improve clarity. 

Cai et al. [7e] investigated electron and hole transfer in various polynucleotide duplexes and compared them with previous results found for salmon sperm DNA, to examine the effect of base sequence on excess electron and hole transfer along the DNA 71-way at low temperature. Electron and hole transfer in DNA was found to be clearly base sequence dependent. In glassy aqueous systems (7M LiBr glasses at 77 K), excess electron-transfer rates increase in the order polydIdC-polydIdC<salmon testes DNAexcess electron and hole transfer rates increase in the order polyC-polyG<salmon testes DNATransfer distances at 1 min and distance decay constants for electron and hole transfer from base radicals to MX in polynucleotides-MX and DNA-MX at 77 K are derived and compiled in Table 3. This table clearly shows that the electron-transfer rate from donor sites decreases in... 

BIVALIRUDIN Bivalirudin (angiomax) is a synthetic, 20-amino-acid polypeptide that directly inhibits thrombin. Bivalirudin contains the sequence Phe -Pro -ArgLPro, which occupies the catalytic site of thrombin, followed by a polyGly linker and a hirudin-like sequence that binds to exosite I. Thrombin slowly cleaves the Arg -Pro peptide bond and thus regains activity. Bivahrudin is administered intravenously and is used as an alternative to heparin in patients undergoing coronary angioplasty. The tj of bivahrudin in patients with normal renal function is 25 minutes dosage reductions are recommended for patients with moderate or severe renal impairment. 

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