SATA modification

Figure 1.64 SATA modification of rabbit polyclonal IgG with the resultant sulfhydryl incorporation level.

The following protocol represents a generalized method for protein thiolation using SATA. For comparison purposes, contrast the variation of this SATA modification method as outlined in Chapter 20, Section 1.1 for use in the preparation of antibody-enzyme conjugates. 

Conjugates of (strept)avidin with these fluorescent probes may be prepared by activation of the phycobiliprotein with N-succinimidyl 3-(2-pyridyldithio)propionate (SPDP) to create a sulf-hydryl-reactive derivative, followed by modification of (strept)avidin with 2-iminothiolane or SATA (Chapter 1, Section 4.1) to create the free sulfhydryl groups necessary for conjugation. The protocol for SATA modification of (strept)avidin can be found in Section 3.1, this chapter. The procedure for SPDP activation of phycobiliproteins can be found in Chapter 9, Section 7. Reacting the SPDP-activated phycobiliprotein with thiol-labeled (strept)avidin at a molar ratio of 2 1 will result in highly fluorescent biotin binding probes. 

T Sata, Modification of properties of ion exchange membranes. III. Interaction between ion exchange membranes and surface active agents, Colloid Polym. Sci., 1978, 256, 52-67 YD. Grebenyuk, R.D. Chebotareva, S. Peters and V Linkov, Surface modification of anion exchange membranes to enhance anti-fouling characteristics, Desalination, 1998, 115, 313. 

T. Sata, Modification of properties of ion-exchange membranes, Doctoral Thesis, 1975, p.10 V Svetlicic and Z. Ronrad, Study of the electrical resistance of alkaline earth ions in cation exchange membranes, J. Membr. Sci., 1979, 5, 129-134. 

Although amine-reactive protocols, such as SATA thiolation, result in nearly random attachment over the surface of the antibody structure, it has been shown that modification with up to 6 SATAs per antibody molecule typically results in no decrease in antigen binding activity (Duncan et al., 1983). Even higher ratios of SATA to antibody are possible with excellent retention of activity. 

Oligonucleotides containing amine groups introduced by enzymatic or chemical means may be modified with SATA (Chapter 1, Section 4.1) to produce protected sulfhydryl derivatives. The NHS ester end of SATA reacts with a primary amine to form a stable amide bond. After modification, the acetyl protecting group can be removed as needed by treatment with hydroxylamine under mildly alkaline conditions (Fig. 401). The result is terminal sulfhydryl groups that can be used for subsequent labeling with thiol-reactive probes or activated-enzyme derivatives (Kumar and Malhotra, 1992). 

T. Sata, Y. Kagiyama, F. Kurokawa and K. Takata, Jpn. Pat. JP 61-18930 (examined application) T. Sata and Y. Yamamoto, Modification of properties of ion exchange membranes. VIII. Change in properties of anion exchange membranes on introduction of hydrophobic groups, J. Polym. Sci., Polym. Phys. Ed., 1989, 27, 2229-2241. 

T. Sata and R. Izuo, Modification of transport properties of ion exchange membranes. XII. Ionic composition in cation exchange membranes with and without a cationic polyelectrolyte layer at equilibrium and during electrodialysis, J. Membr. Sci., 1989, 45, 209. 

Y. Mizutani, R. Yamane, T. Sata and R. Izuo, Cation exchange membrane to selectively permeate hydrogen ions and electrodialysis method to selectively permeate hydrogen ions, Jpn. Pat. JP 47-3801 (examined application) Z. Ogumi, Y. Uchimoto, M. Tsujikawa, K. Yasuda and Z. Takehara, Modification of ion exchange membrane surface by plasma process. Part 3. Interfacial resistance of monovalent permselective membrane from Nafion, Bull. Chem. Soc. Jpn., 1990, 63, 2150. 

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