Genetic engineering study

Old, R.W. and SB Piiiinose Principles of Gene Mu mpuhit ion -An Introduction to Genetic Engineering, Studies in Microbiology, Vol. 2, University of California Press, Berkeley, (1981). pp. 1-47. 

The analysis of tomato color mutants found in Solanum lycopersicum or in crosses with related wild species, as well as genetic engineering studies have clarified enormously the bios3uithetic pathway of carotenoids. Carotenoids, as other plastid isoprenoids, derive from isopentenyl diphosphate (IPP). IPP used in the synthesis of these compounds may arise at some developmental stages partly from the mevalonic (MVA) pathway [23], but it is mainly synthesized through the methyler-ythritol-4-phosphate (MEP) pathway [24]. The first enzyme of this pathway. 

Gene Expression Systems. One of the potentials of genetic engineering of microbes is production of large amounts of recombinant proteias (12,13). This is not a trivial task. Each proteia is unique and the stabiUty of the proteia varies depending on the host. Thus it is not feasible to have a single omnipotent microbial host for the production of all recombinant proteias. Rather, several microbial hosts have to be studied. Expression vectors have to be tailored to the microbe of choice. 

Genetic Control. Manipulation of the mechanisms of inheritance of the insect pest populations has occurred most successhiUy through the mass release of steri1i2ed males, but a variety of other techniques have been studied, including the environmental use of chemostetilants and the mass introduction of deleterious mutations, eg, conditional lethals and chromosomal translocations (58 ndash 60) (see Genetic engineering). 

Biological processes are also being studied to investigate abiHty to remove sulfur species in order to remove potential contributors to acid rain (see Air pollution). These species include benzothiophene-type materials, which are the most difficult to remove chemically, as weU as pyritic material. The pyrite may be treated to enhance the abiHty of flotation processes to separate the mineral from the combustible parts of the coal. Genetic engineering (qv) techniques are being appHed to develop more effective species. 

Chemists teamed the basic composition of siik many years ago, but the reasons why this macromoiecuie is so strong, yet fiexibie, are stiii not fuiiy understood. Recent studies indicate that the secret ties in the way the chains of this protein nestie together. Current research efforts focus on using techniques of genetic engineering to repiicate naturai spider siik on a usefui scaie. 

This has been a brief overview of a rich field. Details of enzyme stracture and catalytic activity are studied in laboratories worldwide. Moreover, genetic engineering makes it possible to manufacture key enzymes in large quantities, so enzymes may become industrial catalysts that accomplish reactions rapidly and selectively. 

A new approach to study root exudation of distinct compounds in soil-grown plants uses inoculation of roots with genetically engineered reporter bacteria, which are able to indicate the presence of particular compounds by indicator reactions, such as production of ice-nucleation proteins. This technique has been employed to detect the release of amino acids from roots of soil-grown A vena harbata (56). 

Genetic engineering of PHA synthase proteins in E. coli in combination with a suitable viable-colony staining method for the screening of PHA content [143] will make many methodological tools applicable to PHA biosynthesis genes and proteins and will allow studies on structure to function relation-... 

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