Conjugated, with baker

Huyng-Ba, T., Matthey-Doret, W, Fay, L. B., Bel-Rhlid, R. (2003). Generation of thiols by biotransformation of cystein-aldehyde conjugates with baker yeast. J. Agric. Food Chem., 51, 3629-3635. 

A conjugated 3-oxo group is not easily reduced by yeast however. Clostridium paraputrificum selectively reduces these steroids to the 3a-hydroxy compounds. Reduction of the 17-oxo group to 17/ -hydroxysteroids can be achieved with baker s yeast, while reduction of the 20-oxo group can be performed in most cases with S treptomyces strains. 

Warrington and Olivier (1979) examined the release of lymphotoxin from the lymphocytes of the peripheral blood in patients with hepatitis after isoniazid. In five of six cases there was support of release of lymphotoxin after stimulation of these lymphocytes with isoniazid or isonicotinic acid conjugated with human serum albumin. Baker et al. (1974) had positive results from the macrophage migration inhibition test in only two of six patients after clinical hypersensitivity to isoniazid. 

Michael-type reactions have been achieved with baker s yeast using trifluoroethanol as the co-substrate (Scheme 5.17). These transformations probably are related to the acyloin condensation in that it has been proposed that the trifluoroethanol is initially oxidized enzymically to the aldehyde, which is then converted to a reactive acyl anion that can add to the electrophilic enone in a conjugate manner. The a, -unsaturated ketones are good Michael acceptors, leading to the corresponding y-hydroxyketones (via the diketone intermediate) in moderate yields (26-40%) and good optical purities (e.e. = 79%). The absolute configurations of the products (16) were not determined. 

Singer, J. W., de Vries, P., Kumar, A., Baker, B., Lyim, S., Li, C., and Wallace, S. Poly-L-Glutamic Acid Paclitaxel Conjugate (PG-TXL) A water-soluble biodegradable conjugate with decreased toxicity and enhanced efficacy. 4th International Symposium on Polymer Therapeutics. 2000. 

Wolff AC, Donehower RC, Carducci MK, Carducci MA, Brahmer JR, Zabelina Y, Bradley MO, Anthony FH, Swindell CS, Witman PA, Webb NL, Baker SD. Phase I study of docosahexaenoic acid-paclitaxel a taxane-fatty acid conjugate with a unique pharmacology and toxicity profile. Clin Cancer Res 2003 9(10 Pt 1) 3589-97. 

Shukla, R., Thomas, T.P., Peters, J.L., Desai, A.M., Kukowska-Latallo, J., Patri, A.K., Kotlyar, A., and Baker Jr., J.R. (2006) HER2 specific tumor targeting with dendrimer conjugated anti-HER2 mAb. Bioconjugate Chemistry 17 1109-1115. 

Figure 5.29. PAMAM dendrimer multifunctional conjugates for cancer treatment. The FA group is a folic acid cancer cell target, and FITC is fluorescein isothiocyanate, used as an imaging agent. Also shown (bottom) is the molecular structure for the anticancer drug, taxol, denoting the -OH group that covalently attaches to the dendrimer. Reproduced with permission from Majoros, I. J. Myc, A. Thomas, T Mehta, C. Baker, J. R. Biomacromolecules, 2006, 7, 572. Copyright 2006 American Chemical Society.

Patri AK, Kukowska-Latallo IF, Baker Jr. Targeted drug dehvery with dendrimers comparison of the release kinehcs of covalently conjugated drug and non-covalent drug inclusion complex. Adv. Drug Delivery Rev. 2005 57 2203-2214. 

Baker s yeast reduces conjugated nitro compounds to nitroalkanes and also the C=C unit of conjugated ketones. Other enzymatic reductions are possible. A reductase from Nicotiana tabacum reduced a conjugated ketone to the saturated ketone, with excellent enantioselectivity. Enzyme YNAR-I and NADP-H reduces conjugated nitro compounds to nitroalkanes. ... 

Dendrimers have also been proposed as gene transfection agents and, in 2001, Baker and coworkers showed that complexation with (3-CD improves the efficiency of DNA membrane transport by polyamidoamino (PAMAM) dendrimers [62], This was thought to be due to the smaller size of the dendrimer-DNA particles that form in the presence of (3-CD. A similar concept has been developed extensively by Uekama s group, although they elected to prepare covalent conjugates of PAMAM dendrimers with 0-CD [63-65], Kim and coworkers have also reported on the use of cucurbiturils to improve the gene transfection efficiency of dendrimers [66],... 

A.K. Patri, J.F. Kukowska-Latallo, J.R. Baker Jr., Targeted dmg delivery with dendrimers comparison of the release kinetics of covalently conjugated dmg and non-covalent dmg inclusion complex, Adv. Dmg Deliv. Rev. 57 (2005) 2203-2214. 

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