Relation to sequences

Several specialized programs relating to sequence analysis especially good and fast search for sequence patterns with choice of amino acids in a given position as well as variable separations between them (QUEST)... 

DNase I is an endonuclease that catalyzes the hydrolysis of phosphodiester bonds by nucleophilic attack on 3 O-P. The enzyme activity requires divalent metal ion cofactors such as Mg " and Ca or Mn +. DNase I binds to the minor groove of dsDNA and cleaves each strand independently. The often observed sequence preference and different cleavage rates of DNase I are largely structural and are related to sequence-dependent variations of the double helix such as groove width, local rigidity to bending, radial asymmetry, and accessibility to backbone phosphates (26,29,33,34). 

The reaction of MeO /MeOH with 2-Cl-5(4)-X-thiazoles (122) follows a second-order kinetic law, first order with respect to each reactant (Scheme 62) (297, 301). A remark can be made about the reactivity of the dichloro derivatives it has been pointed out that for reactions with sodium methoxide, the sequence 5>2>4 was observed for monochlorothiazole compounds (302), For 2.5-dichlorothiazole, on the contrary, the experimental data show that the 2-methoxy dehalogenation is always favored. This fact has been related to the different activation due to a substituent effect, less important from position 2 to 5 than from... 

Using the term weakly compact we mean only that every bounded sequence contains a weakly converging subsequence. The same is related to the term - weakly compact. 

This tendency is related to the polarization properties of the monomer substituents (42). Monomers that are dissimilar in polarity tend to form alternating monomer sequences in the polymer chain. An example is the monomer pair acrylonitrile—styrene. Styrene, with its pendent phenyl group, has a relatively electronegative double bond whereas acrylonitrile, with its electron-withdrawing nitrile group, tends to be electropositive. 

The amino acid sequences of hCS-A, hCS-B, and hCS-V are shown in relation to GH in Figure 1. The sequence of hCS-V is predicted from the DNA coding sequence and apparentiy does not possess amino acids 8—55 relative to GH and the other hCS molecules. It is not certain whether hCS-V is expressed or what function it may have. Human CS-A and hCS-B share approximately 85% identity with GH and also possess the disulfide bonds between Cys 53—165 and Cys 182—189 which produce the long and short S—loops characteristic of the PRL/GH family. 

Biosynthesis. CRE is derived from a precursor of 196 amino acids (84,85). This gene contains one copy of CRE, which is flanked by double basic amino acids. The amino acid sequence of the CRE precursor suggests that it may arise from proteins related to POMC and neurophysins (31). The CRE precursor contains a cAMP responsive element which aHows stimulation of mRNA synthesis when intraceHular levels of cAMP are increased (86). 

Mass spectral fragmentation patterns of alkyl and phenyl hydantoins have been investigated by means of labeling techniques (28—30), and similar studies have also been carried out for thiohydantoins (31,32). In all cases, breakdown of the hydantoin ring occurs by a-ftssion at C-4 with concomitant loss of carbon monoxide and an isocyanate molecule. In the case of aryl derivatives, the ease of formation of Ar—NCO is related to the electronic properties of the aryl ring substituents (33). Mass spectrometry has been used for identification of the phenylthiohydantoin derivatives formed from amino acids during peptide sequence determination by the Edman method (34). 

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