Biotechnology microbial synthesis

Kowshik, M., Deshmukh, N., Vogel, W., Urban, J., Kulkami, S.K., and Paknikar, K.M. 2002. Microbial synthesis of semicondnctor CdS nanoparticles, their characterization, and their use in the fabrication of an ideal diode. Biotechnology and Bioengineering, 78 583-8. 

Steinbtichel A, Hein S (2001) Biochemical and molecular basis of microbial synthesis of polyhy-droxyalkanoates in microorganisms. Adv Biochem Eng Biotechnol 71 81-123 Steinbtichel A, Ltitke-Eversloh T (2003) Metabolic engineering and pathway construction for biotechnological production of relevant polyhydroxyalkanoates in microorganisms. Biochem Eng J 16 81-89... 

Saito Y, Doi Y (1994) Microbial synthesis and properties of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) in Comamonas acidovorans. Int J Biol Macromol 16 99-104 Saito Y, Nakamura S, Hiramitsu M, Doi Y (1996) Microbial synthesis and properties of poly(3-hydroxybutyrate-co-4-hydroxybutyrate). Polymer Int 39 167-174 Salehizadeh H, Van Loosdrecht MCM (2004) Production of polyhydroxyalkanoates by mixed culture recent trends and biotechnological importance. Biotechnol Adv 22 261-279... 

Demain AL, Scanchez S. Microbial synthesis of primary metabolites Current advances and future prospects. In Fermentation Microbiology and Biotechnology, El-Mansi EMT, Bryce CFA, Demain AL, Allman AR, Eds. CRC, New York, pp. 99—130. 

A third advancement in microbial biotechnology of steroid production was the abiUty to introduce a 16a-hydroxyl group microbiologicaHy (163). Modifications of the liP-hydroxylation, 16a-hydroxylation 1,2-dehydrogenation microbial processes are used for the synthesis of hydrocortisone, prednisolone, triamcinolone, and other steroid pharmaceuticals. A few microbial transformations that have been used to manufacture steroids are Hsted in Table 1 (164). 

The availability of ctetq) advanced synthons that carry the required chirality is an advantage, particularly in projects aimed at industrial total synthesis. Natural products are often used as synthons, ideally fi om a renewable source, such as microbial fermentations. In a few cases, biotechnology has become an ahemative source. The total theses of the antitumor agent esperamicin A and the immunosuppressant FK-506 are exanq>les. In both cases, the synthon was quinic acid (Barco 1997), cheaply obtained by biotechnology (Chapter 14.1.e) rather than fi om the environmentally noxious extraction fi om the bark of Cinchona spp. Used to build up combinatorial libraries, quinic acid has gained further inq)ortance in organic thesis (Phoon 1999). 

Lipases play an important role in organic synthesis and also in flavour biotechnology. Pig pancreatic extract and especially many microbial lipases are used for ester hydrolysis, esterification (alcohol and acid), transesterification (ester and... 

The biotechnological synthesis of lactones has reached a high standard. Besides microbial production, lactones can also be enzymatically produced. For instance, a lipase-catalysed intramolecular transesterification of 4-hydroxy-carboxylic esters leads enantioselectively (ee>80%) to (S)-y-lactones the chain length may vary from C5 to Cl 1 [13]. y-Butyrolactone can be produced in that way with lipase from Mucor miehei [30]. 

Another Important attribute of whole cell/enzyme systems is for the production of optlcally-actlve compounds. As early as the 1950s, the synthesis of optically active gamma- and delta-lactones by microbiological reduction was demonstrated (18). Production of optlcally-pure L-glutamate for use in the flavor enhancer MSG by microbial means is another testimonial to this potential of biotechnology. 

Confronted with the often expensive methods used to synthesise nanomaterials, which involve the use of hazardous chemicals, there is a growing concern to develop environmental-friendly and sustainable methods for the synthesis of nanoparticles of different compositions, sizes, shapes, and controlled dispersity, particularly using a green chemistry approach which interconnects nanotechnology and microbial biotechnology. 

For biotechnological synthesis, there is a superb database containing information on miaobial biocatalytic reactions and biodegradation pathways for primarily xenobiotic, chemical componnds. It is called the University of Minnesota Biocatalysis/Biodegradation Database (UM-BBD) at can be fonnd at http //nmbbd.ahc.umn.edu/search/index.html. The goal of the UM-BBD is to provide information on microbial enzyme-catalyzed reactions that are important for biotechnology. 

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