Crosslinking Studies

Figure 8.20 (A) Generic chemical structure of the y-secretase inhibitors described by Seiffert et al. (2000). (B) y-Secretase inhibitor incorporating a benzophenone photoaffinity label for crosslinking studies.

Fig. 16. Schematic depiction of the murine hemopexin receptor. The results of crosslinking studies (163) suggested that the murine receptor was composed of two subunits (a and p). The larger (65 kDa) is designated as a and is disulfide-linked to the smaller P subunit, which contains a free sulfhydryl. Hemopexin (which has no free sulfhydryl groups) can be crosslinked to the a-subunit but may also bind to the p-subunit.

Isocyanate Crosslinkers. A wide variety of both aromatic and aliphatic Isocyanate crosslinkers are used in coatings (4). Aliphatic isocyanates are used when external durability is required. The isocyanate crosslinker studied in this work is the biuret of hexamethylene diisocyanate (Figure 1). Although resins based on triisocyanurates have been claimed to be superior in durability (,22.) > biuret based triisocyanates are more commonly used. Urethane coatings are generally formulated with a ratio of isocyanate to hydroxy of around 1 1. 

Table 1. Compressive properties from crosslinking studies...

Steinert, P. M., Marekov, L. N., Fraser, R. D. B., and Parry, D. A. D. (1993a). Keratin intermediate filament structure Crosslinking studies yield quantitative information on molecular dimensions and mechanism of assembly. /. Mol. Biol. 230, 436-452. 

In extending the PtR assignments using standard DNA sequential assignment methods Fig. 77), we found several structural changes and distinct chemical shifts around the platination site. We report these features in Table 3 and compare them to those of other duplexes with d(G pG ) crosslinks studied by NMR methods [51][71-74][77][105][107]. These duplexes are generically referred to here as PtD (see Table 1 for specific sequences and abbreviations). In addition, a duplex with a d(A pG ) crosslink has been studied by NMR spectroscopy, and these data are also included in the... 

In order to evaluate the possible use of MAGME-polymers in resist applications, crosslinking studies were conducted on thin films (1 ym ), spinn-coated on silicon wafers. Poly-MAGME is water soluble and most of its co-polymers are soluble in alcohols (Table 3) making the materials relatively attractive to work with from a production point of view. 

Crosslinking studies were supported in part by a Vincent Brown Coffin faculty grant provided by the University of Hartford. 

The MMO system also has a 38-kDa reductase component (MMOR) which has one FAD and one [2Fe-2S] cluster as prosthetic groups [17, 23, 24]. MMOR is readily reduced by NADH and transfers electrons to MMOH. Crosslinking studies show that it has a specific binding site on the MMOH y -subunit [25]. The third component is a 15-kDa protein without cofactors or metal ions termed component B (MMOB). This protein performs a number of regulatory functions through formation of a complex with the a-subunit of MMOH [5, 25]. Some of these functions will be described below, but the net effect is to greatly accelerate the turnover reaction and to increase the product yield from about 40% to nearly 100% when MMOR is also present [26, 27]. 

Han KC, Shen JR, Ikeuchi M et al. Chemical crosslinking studies of extrinsic proteins in cyanobacterial photosystem II. FEBS Lett 1994 355 121-124. 

Medium Chain Acyl Coenzyme A Dehydrogenase Complex, Preliminary Evidence from Crosslinking Studies... 

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