Reverse transcriptase endonuclease

The pol gene, responsible for formation of viral enzymes protease, reverse transcriptase, and endonuclease (integrase). 

Rennin—see chymosin Repertoire selection 415-418 Reporter group 276 Resonance Raman spectra 476 Restriction endonucleases 406-408 Restriction fragment 408 Retention of stereochemical configuration 253, 254 Reverse genetic s 438 -442 Reverse transcriptase 3 8 Rhizopus-pepsin 486, 490 Ribonuclease A 9... 

Fig. 3. Universal primers for PCR amplification of endogenous retroviral reverse transcriptase. The primers anneal within the retroviral reverse transcriptase gene at the position indicated by the thick lines in Fig. 2. The degenerate primer pair has been used successfully,21 but it gives a number of nonspecific products. Substitution of inosine at some of the degenerate positions increases the effective concentration of primer. Xba and coRI restriction endonuclease cleavage sites are underlined.

Heparin Growth factors, coagulation faaors, lipoproteins, DNA polymerase, DNA ligase, RNA polymerases, restriction endonucleases, polynucleotide kinase, lipoprotein lipase, hepatic triglyceride lipase, reverse transcriptase, hyaluronidase, neurauninidase, trypsin, pepsin, fumarase, lectin from chicken liver and embryonic chicken muscle, platelet-secreted antiheparin proteins, platelet-endoglycosidase... 

Restriction endonucleases and DNA ligase Cutting, rejoining DNA Reverse transcriptase Conversion of mRNA into cDNA Chemical DNA synthesis Oligonucleotides Polymerase chain reaction (PCR)... 

Intron encoded maturases. These proteins, which are normally encoded by an open reading frame (ORF) within the intron, bind specifically their own RNA and promote formation of critical tertiary contacts. In addition, most of these proteins have endonuclease and reverse-transcriptase domains, which allow intron mobility (i.e., retrotransposition and retrohom-ing) by a mechanism termed target primed reverse transcription (TPRT) (vide infra). 

The use of isolated enzymes to form or cleave P-O bonds is an important application of biocatalysts. Restriction endonucleases, (deoxy)ribonucleases, DNA/ RNA-ligases, DNA-RNA-polymerases, reverse transcriptases etc. are central to modern molecular biology(1). Enzyme catalyzed phosphoryl transfer reactions have also found important applications in synthetic organic chemistry. In particular, the development of convenient cofactor regeneration systems has made possible the practical scale synthesis of carbohydrates, nucleoside phosphates, nucleoside phosphate sugars and other natural products and their analogs. This chapter gives an overview of this field of research. 

Arber and Smith Temin and Baltimore Khorana Discovered restriction endonucleases Discovery of reverse transcriptase in retroviruses Synthesis of first gene... 

Initially discovered in extracts of calf thymus as a contaminating enzyme during the purification of RNA polymerase (1,2), RNase H has since been found almost ubiquitously in lower and higher eukaryotes as well as in prokaryotes. A single cell type may have one or more species of RNases H residing in the cell nucleus and/or cytosol. Some RNases H have a single ribonucleolytic reaction specificity, whereas others are associated with DNA polymerase activities. Cellular RNases H, for example, from E. coli and calf thymus, are endonucleases the retroviral reverse transcriptase-associated RNases H can function as both exo- and endoribo-nucleases depending on the type of substrates available. 

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