Reporter groups, introduction

In recent years, silica sol-gel-based inorganic-organic hybrid materials have also been reported. The introduction of various functional groups into organic alkoxide has led to organically modified sol-gel glasses (ormosils). Some of the ormosil monomers and ormosil formations can be found in Fig. 16.3. Redox molecules can be coupled with the ormosil monomer functional group. The immobilized redox molecules can... 

The Tsogoeva group, in 2006, reported the introduction of newly designed bifunctional secondary amine-functionalized proline-based thioureas (95 and 96) and the primary amine-functionalized thioureas (97-99) for catalysis of the asymmetric addition of ketones to trans-P-nitrostyrenes (Figure 6.30) [260, 261]. Using... 

In 1994, Weidenbruch et al. reported that introduction of two 2,4,6-tri-tert-butylphenyl groups onto the tin atom led to the successful isolation of 167, which is the first example of kinetically stabilized monomeric diarylstannylene characterized in the solid state. Note that Sn NMR spectrum of 167 shows two signals at 961 and 1105 ppm instead of a singlet expected at room temperature in solution. The striking feature of 167 is its partial isomerization into a sterically less encumbered stannylene 168 in solution (Scheme 14.73). The two signals of 167 coalesce... 

Aliphatic hydroxyl groups cannot normally be selectively modified except in certain special cases such as the serine proteinases. In anhydrous formic acid, the A,O-acyl migration that occurs in strong sulfuric or phosphoric acid apparently does not occur. Instead there is formylation of the serine and threonine residues (208). Enzymically inactive aggregates are produced, but the reaction is reversed in aqueous solution at neutral pH and the activity returns. Josefsson reported the introduction of 29 formyl groups in RNase (209) as compared to the total of 25 Ser and Thr residues. This identification of reaction sites is not clear, however, since the number of formyl groups introduced into lysozyme far exceeded the Ser-Thr total. 

For the first time, inverse substrates provide a general method for the specific introduction of an acyl group into the trypsin active site without recourse to cation-containing acyl compounds. The preparation of various new acyl enzymes is expected to lead to the discovery of novel features of the enzymatic reaction mechanism. In addition, any desired reporter groups might be specifically introduced into the trypsin... 

The observed shift increments and decrements, due to the introduction of sialic acid, for structural-reporter groups of neighboring residues are of the same order of magnitude as for the step from 17 to 21, but larger for H-l of Man-4 than for H-l of Man l. In this case, also... 

As compared to the spectrum of the asialo analog 17, the introduction of NeuAc at 0-3 of Gal-6 gives rise to a limited number of effects on the chemical shifts of structural-reporter groups of neighboring sugar residues, namely, a shift increment for H-l of Gal-6 (A8 0.076... 

On comparing the n.m.r. data for 47 with those for the /3 anomer of 18 (see Table VIII), some characteristic shift increments and decrements of reporter groups may be ascribed to the introduction of Fuc a-(l- 3)-linked to GlcNAc-5. Although the chemical shift of H-l of 5 ... 

The chemical shifts of the structural-reporter groups of Fuc in a-(1—>2) linkage to Gal of an N-acetyllactosamine branch, together with the influences of its introduction upon the chemical-shift values of reporter groups of neighboring residues, are summarized in Table XXI. 

The introduction of a (sialylated) N-acetyllactosamine unit /3-( 1—>3)-linked to Gal-a gives rise to very few alterations in chemical shifts, coupling constants, and line widths of structural-reporter groups of neighboring residues that can be used for the localization of additional N-acetyllactosamine units in more-complex structures (compare Refs. 91-92a). The influences of this unit are almost exclusively re-... 

Owing to the introduction of Man-4, the characteristically shaped H-2 signal of Man-3 in particular undergoes a downfield shift, from 8 4.076 for 61 to 8 4.251, whereas the chemical shift of H-l of Man-3 is only slightly affected (A8 0.01 p.p.m.) (compare the influence ascribed to the introduction of Man-A upon the reporter groups of Man-4, in the step from 3 to 61). The effects of introduction of Man-4 into 61 are identical to those described for the steps from 18 to 20 (see Table VIII) and from 22 to 24 (see Table IX). 

Owing to the introduction of Man-C, the structural-reporter-group signals of Man-4 undergo downfield shifts (A8H-1,0.243 A8H-2, 0.037 p.p.m.). The H-l and H-2 signals of Man-3 are both shifted slightly up-... 

Introduction of Reporter Groups. A reporter group is one that is attached to (or sometimes noncovalently associated with) a larger molecule for conveying information about the larger molecule s changes in conformation, environment, or association with ligands. These include... 

In essence, the introduction of the avidin-biotin complex into a given system does not contribute a factor of specificity to an immunochemical reaction rather, its involvement serves to mediate between the recognition system (i.e., cintibody-cintigen complex) ind a given probe or reporter group. Such mediation usually results in an amplified or improved signal. 

A plethora of methods are now available for labelling oligonucleotide probes for hybridisation experiments. Many of these procedures are compatible with automated DNA synthesis and the introduction of multiple reporter groups provides a means of amplifying the signal from the probe. 

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