Gyrase

DNA fibers DNA fingerprinting DNA gyrase DNA ligase DNA ligases DNA polymerase... 

DNA is cut and a conformational change allows the DNA to pass through. Gyrase religates the DNA and dien releases it. 

A relaxed, circular, double-stranded DNA molecule (1600 bp) is in a solution where conditions favor 10 bp per turn. What is the value of Lq for this DNA molecule Suppose DNA gyrase introduces 12 negative snpercoils into this molecule. What are the values of L, W, and T now What is the snperhelical density, cr ... 

In the course of synthesizing DNA-gyrase inhibitors Hogberg, Mitscher, and coworkers determined that an effective means of constructing the core of their inhibitors was via a K-R reaction. Under mild conditions, keto ethylester 52 was acylated using acetic formic anhydride in the presence of sodium formate to deliver chromone 53 in 75% yield. 

Gyrase is another term for bacterial topoisomerase II. The enzyme consists of two A and two B subunits and is responsible for the negative supercoiling of the bacterial DNA. Negative supercoiling makes the bacterial DNA more compact and also more readily accessible to enzymes that cause duplication and transcription of the DNA to RNA. 

The enzymes gyrase and topoisomerase IV can be protected from fluoroquinolone inhibition by a small protein belonging to the pentapeptide-repeat family of... 

II ( gyrase ) II Tetramer (2 GyrA 2 GyrB subunits) gyrA/ gyrB Introduces negative supercoils into DNA... 

The fluoroquinolones exert their bactericidal (bacteria-destroying) effect by interfering with an enzyme (DNA gyrase) needed by bacteria for the synthesis of DNA. 

Hallett, P., Mehlert, A., Maxwell, A. (1990). E. colt cells resistant to the DNA gyrase inhibitor, ciprofloxacin, overproduce a 60 IcD protein homologous to GroEL. Mol. Microbiol. 4,345-353. 

Use chemotherapeutic (Proteus bacteria infections, gyrase inhibitor)... 

Simon, H., L. Kittler, E. Baird, P. Dervan, and C. Zimmer Selective inhibition of DNA gyrase in vitro by a GC specific eight-ring hairpin polyamide at nanomolar concentration. FEBS Lett. 2000, 471, 173-176. 

The amplification of genetic information, i.e., the replication of parent DNA molecules, is achieved by means of an entire set of enzymes. The major players are a DNA-gyrase for unwinding of the double helix, proteins to separate the two antiparallel DNA strands at the replicational junction, single-stranded binding proteins (SSB) that prevent the... 

Aminoimidazole-4-Carboxamide Ribonucleotide Transformylase Carbonic Anhydrase II DNA Gyrase... 

Chromosome function Quinolones Metronidazole (also ) Nitrofu rantoin Rifampicin (also ) 5-Fluorocytosine Inhibit DNA gyrase DNA strand breakage DNA strand breakage Inhibits RNA polymerase Inhibits DNA synthesis No action on mammalian equivalent Requires anaerobic conditions not present in mammalian cells No action on mammalian equivalent Converted to active form in fungi... 

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