Molecular biology techniques molecules

The expression of many of these molecules has been studied during various stages of differentiation of normal neutrophils and also of corresponding leukemic cells employing molecular biology techniques (eg, measurements of their specific mRNAs). For the majority, cDNAs have been isolated and sequenced, amino acid sequences deduced, genes have been localized to specific chromosomal locations, and exons and intron sequences have been defined. Some important proteinases of neutrophils are listed in Table 52-12. 

Figure 7.2-2. Central Dogma. The genes located on the chromosomes are transcribed into mRNA, which is exported from the nucleus to the cytosole where it is translated. Thanks to molecular biology techniques, it is possible to bring exogenous genetic information. Foreign DNA molecules must cross two membranes the cytoplasmic and the nuclear envelopes, whereas mRNA must cross only the cytoplamic membrane to be active.

Plasmid DNA (pDNA) and messenger RNA (mRNA) are attractive tools for therapy because they are simple molecules that are easy to produce, store, detect, and manipulate using molecular biology techniques. They can be used to quickly turn into a drug any genetic information. Alternatives to pDNA and mRNA are virus- or bacteria-derived vehicles that can contain the genetic information to be expressed as a drug. The drawbacks of these methods are as follows ... 

The development of automated soUd phase synthesis of nucleic acids and chemical strategies to incorporate fluorophores at any position along their length, together with the wide array of molecular biological techniques available for their modification has resulted in a system highly amenable to single molecule fluorescent studies. By contrast, proteins, to which we now turn our attention, are rarely synthesized in vitro and thus a different approach needs to be taken. 

Soluble enzymes are much easier to study, so more is known of the first type, but from many studies with a variety of spectroscopic. X-ray and molecular biological techniques, it seems the mechanism of reaction is the same in both types. Although the full story of the enzymes is not yet known, the description here summarizes our present knowledge of membrane-bound fatty acid desaturases found in insects. The description is of a A9-desaturase, the most common type, which converts stearic acid to oleic acid. The location of the double bond is measured from the carboxylate end of the molecule. Palmitic acid with the same enzyme gives palmitoleic acid. If an unnatural Cjy or C19 acid is supplied to the... 

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