Amylose resin

Figure 14.7 Schematics depicting the assembly of QD-protein conjugates that engages in FRET near a surface. Step 1, the glass slide waveguide is coated with Avidin. Step 2, attach biotinylated MBP to Avidin on the surface as a linker. Step 3, self-assemble MBP-dye and avidin onto the QD surfaces. Step 4, purify the QD conjugate solution from 3 over amylose resin. Step 5, allows the QD assembly to attach to the MBP-Bt via its surface Avidin and wash away excess reagents. Adapted from reference 32.

Because HMM contains an MBP domain, affinity chromatography using amylose resin also could be used as an alternate or additional purification step, although we have not done this. 

For example, MBP and GST fusion proteins may be tested by mixing the respective crude lysates, purifying the MBP fusion protein using amylose resin, and assessing co-purification by immunoblot analysis using anti-GST primary antibodies. 

The His-tagged MBP-MS2 coat fusion protein (HMM) used in this method was created to allow the protein to be immobilized on both Ni2+ or amylose affinity resins. HMM is a 59-kDa protein containing an NT-terminal hexahistidine (6x His) tag, a central maltose-binding protein (MBP) domain, and a C-terminal MS2 coat protein containing the V29/dIFG mutations, which prevent protein multimerization and increase its affinity for RNA (Lim and Peabody, 1994). The protein is expressed in E. coli from plasmid pHMM, which confers kanamycin resistance, and purified using affinity chromatography. 

In the context of this chapter, the use of thermoplastic starch in blends with thermoplastic resins is of the main interest. As shown in Table 16.11, several blends have been developed, e.g., with vinyl alcohol copolymers (EVAl), polyolefins, aliphatic polyesters such as poly-e-caprolactone (PCL) and its copolymers, or polymers of glycols (e.g., 1,4-butanediol) with succinic, sebacic, adipic, azelaic, decanoic or brassihc acids, PCL + PVC. Compatibilization is possible by amylose/EVAl V-type complexes, starch grafted polyesters, chain extenders like diisocyanates, epoxies, etc. [Bastioli et al., 1992, 1993]. 

Amilan Amino resins Amoco-AI-10 Amodel Amylopectin Amylose Apical a-PP... 

Pack 1-2 mL bed volumes ofthe appropriate resin (glutathione-Sepharose for GST, amylose for MBP) in a disposable column... 

Starch is composed of Amylose and Amylopectin. Amylose is preponderantly a linear polymer of several thousand D-glucose units mainly a-(l - 4) linked. Amylopectin is a branched polymer composed largely of a-D-(l 4)-linked glucose units. The branch is a-(l 6) and occurs at the 6 position every 20-25 glucose units. Pullulanase, i -enzyme and Isoamylase hydrol. the a-D-(l 6) linkages. Polymeric. Minimum formula given. Graft polymers with acrylates are used as water-absorbent resins. 

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