Production of secondary metabolites

This is as far as we want to take our discussion of the development of deep cultures for the production of penicillin in this chapter. It is an aspect of the production of secondary metabolites, such as penicillin, more appropriately dealt with in the technology texts in the BIOTOL series. 

I. PRODUCTION OF ANTIBIOTICS. The production of secondary metabolites with antimicrobial properties has long been recognized as an important factor in disease suppression (see Chap. 7). Metabolites with biocontrol properties have been isolated from a large number of rhizosphere microorganisms, including the fluorescent pseudomonads (Table 2). Further discussion is not given here since this is the subject of recent reviews (122,123). 

Streptomyces strains are Gram positive [54], they have good secretion capacities and extensive fermentation knowledge has been accumulated. Mostly, they were used for the production of secondary metabolites with potent biological activities, such as antibiotics, immunosuppressors or pesticides. Constitutive [55] and inducible [56] expression is possible. Up to 40% of the total soluble cellular protein was reported in the case of inducible expression. 

Nielsen, J. (1998) The role of metabolic engineering in the production of secondary metabolites. Current Opinion in Microbiology, 1, 330—336. 

These dynamic strategies also play important roles in the chemical defense of benthic organisms. Only in recent years have marine scientists started to apply methods that allow these defensive strategies to be monitored. This opens the field for the identification of signals that play a role in species-species interactions in the marine environment and for the elucidation of hormones responsible for regulating the production of secondary metabolites. 

Although herbivore pressure is more intense and is exerted by a more diverse assemblage of consumers in the tropics (Liming 1990), it is now known that herbivory fails to fully explain the production of secondary metabolites, and that these... 

Nagle DG, Paul VJ (1999) Production of secondary metabolites by filamentous tropical marine cyanobacteria ecological functions of the compounds. J Phycol 35 1412-1421 Nagle DG, Camacho FT, Paul VJ (1998) Dietary preferences of the opisthobranch mollusc Stylocheilus longicauda for secondary metabolites produced by the tropical cyanobacterium Lyngbya majuscula. Mar Biol 132 267-273... 

Determining costs of secondary metabolites is inherentiy difficult as a result of the variable responses, multiple physiological roles of the metabolites, as well as the different types of costs involved in the production of secondary metabolites (production, transport, storage, maintenance) (Strauss et al. 2002). Emerging studies are now taking more of these variables into consideration. For example, work with clonal populations of D. pulchra has estimated costs of furanone production in relation to chemical defense and phenotype by investigations of reproductive... 

The Polyketide Pathway One metabolic process that has received much attention from natural product chemists is the production of secondary metabolites via polyketide synthase (PKS) enzymes. Polyketide synthases condense small starting... 

Waterman PG, Mole S (1989) Extrinsic factors influencing production of secondary metabolites in plants. In Bernays EA (ed) Insect-plant interactions. CRC, Boca Raton, FL, pp 107-164 Weidner K, Lages BG, da Gama BAP, Molis M, Wahl M, Pereira RC (2004) Effect of mesograz-ers and nutrient levels on induction of defenses in several Brazilian macroalgae. Mar Ecol Prog Ser 283 113-125... 

Presently, there are three microbial phylogenetic hot spots known for the production of secondary metabolites ... 

Saito, K. Yamazaki, M. Miuakoschi, I. (1992) Transgenic medicinal plants Agrobacterium-mediaXed foreign gaie transfer and production of secondary metabolites. J. Nat. Prod., 55, 149-62. 

The seasonal variation (collection of plants at different times or seasons), is a very significant factor in the percentage and production of secondary metabolites [Mitscher, Pillai, Shankel,... 

It is widely recognized that plant cells are potentially rich sources of commercially important secondary metabolites. The production of secondary metabolites could be controlled by a mechanism by which... 

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