scholarly journals Nucleotide sequence of the Staphylococcus aureus gyrB-gyrA locus encoding the DNA gyrase A and B proteins.

1992 ◽  
Vol 174 (5) ◽  
pp. 1596-1603 ◽  
Author(s):  
E E Margerrison ◽  
R Hopewell ◽  
L M Fisher
Keyword(s):  
Staphylococcus Aureus ◽  
Nucleotide Sequence ◽  
Dna Gyrase ◽  
Gyrase A

scholarly journals Role of the Extended α4 Domain of Staphylococcus aureus Gyrase A Protein in Determining Low Sensitivity to Quinolones

2006 ◽  
Vol 50 (2) ◽  
pp. 600-606 ◽  
Author(s):  
Jacob Strahilevitz ◽  
Ari Robicsek ◽  
David C. Hooper
Keyword(s):  
Staphylococcus Aureus ◽  
Acquired Resistance ◽  
Dna Gyrase ◽  
Wild Type ◽  
Topoisomerase Iv ◽  
E Coli ◽  
Gyrase A ◽  
Low Sensitivity ◽  
Emergence Of Resistance

ABSTRACT Fluoroquinolones target two bacterial type II topoisomerases, DNA gyrase and topoisomerase IV. Acquired resistance to quinolones occurs stepwise, with the first mutation occurring in the more sensitive target enzyme. To limit the emergence of resistance, quinolones should ideally possess dual activities against the two enzymes. For reasons that are as yet unclear, Staphylococcus aureus gyrase is less sensitive to quinolones than topoisomerase IV, counter to its greater sensitivity in Escherichia coli, thereby limiting the use of quinolones for the treatment of staphylococcal infections. Mutations in the α4-helix domain of the GyrA subunit of gyrase are important in determining quinolone resistance. We replaced an extended region encompassing the α4 domain in the E. coli GyrA protein with its homolog in S. aureus and tested for its ability to complement a thermosensitive gyrase and its catalytic and noncatalytic properties. Purified gyrase reconstituted with chimeric GyrA was more resistant to ciprofloxacin than wild-type gyrase at both inhibition of catalytic activity and stimulation of cleavage complexes, and this difference was more apparent in the presence of K+-glutamate. The chimeric GyrA subunit was able to complement thermosensitive gyrase, similar to wild-type GyrA. Without supplemental K+-glutamate the MICs of ciprofloxacin for thermosensitive E. coli complemented with chimeric DNA gyrase were equal to those for E. coli complemented with wild-type gyrase but were twofold higher in the presence of K+-glutamate. Our findings suggest that the extended α4 domain of S. aureus GyrA is responsible, at least in part, for the increased resistance of S. aureus gyrase to quinolones and that this effect is modulated by K+-glutamate.

Cloning and nucleotide sequence of the DNA gyrase gyrA gene from the fish pathogen Aeromonas salmonicida.

1996 ◽  
Vol 40 (5) ◽  
pp. 1126-1133 ◽  
Author(s):  
H Oppegaard ◽  
H Sørum
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Nucleotide Sequence ◽  
Amino Acid Sequence ◽  
Dna Gyrase ◽  
Aeromonas Salmonicida ◽  
Fish Pathogen ◽  
Gyra Gene ◽  
Calculated Molecular Mass ◽  
Gyrase A

The DNA gyrase gyrA gene from the fish pathogen Aeromonas salmonicida 2148/89 was cloned, and the nucleotide sequence was determined. An open reading frame of 2,766 nucleotides was identified and was found to encode a protein of 922 amino acids with a calculated molecular mass of 101.1 kDa. The derived amino acid sequence shared a high degree of identity with other DNA gyrase A proteins, in particular, with other gram-negative GyrA sequences. When the amino acid sequence of A. salmonicida GyrA was compared with that of Escherichia coli GyrA, a number of conserved residues were present at identical coordinates, including the catalytic Tyr residue at position 122 (Tyr-122) and residues whose substitution confers quinolone resistance, notably, Ser-83, Ala-67, Gly-81, Asp-87, Ala-84, and Gln-106. An intragenic region corresponding to 48 amino acids, which is not present in E. coli or other bacteria, was identified in the C-terminal part of A. salmonicida GyrA. This intragenic region shared sequence identity with various DNA-binding proteins of both prokaryotic and eukaryotic origins.

scholarly journals Cloning and simplified purification of Escherichia coli DNA gyrase A and B proteins.

1984 ◽  
Vol 259 (14) ◽  
pp. 9199-9201 ◽  
Author(s):  
K Mizuuchi ◽  
M Mizuuchi ◽  
M H O'Dea ◽  
M Gellert
Keyword(s):  
Escherichia Coli ◽  
Dna Gyrase ◽  
Gyrase A

scholarly journals Differential behaviors of Staphylococcus aureus and Escherichia coli type II DNA topoisomerases.

1996 ◽  
Vol 40 (12) ◽  
pp. 2714-2720 ◽  
Author(s):  
F Blanche ◽  
B Cameron ◽  
F X Bernard ◽  
L Maton ◽  
B Manse ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Strong Support ◽  
Dna Gyrase ◽  
Dna Supercoiling ◽  
Type Ii ◽  
Topoisomerase Iv ◽  
E Coli ◽  
Dna Relaxation

Staphylococcus aureus gyrA and gyrB genes encoding DNA gyrase subunits were cloned and coexpressed in Escherichia coli under the control of the T7 promoter-T7 RNA polymerase system, leading to soluble gyrase which was purified to homogeneity. Purified gyrase was catalytically indistinguishable from the gyrase purified from S. aureus and did not contain detectable amounts of topoisomerases from the E. coli host. Topoisomerase IV subunits GrlA and GrlB from S. aureus were also expressed in E. coli and were separately purified to apparent homogeneity. Topoisomerase IV, which was reconstituted by mixing equimolar amounts of GrlA and GrlB, had both ATP-dependent decatenation and DNA relaxation activities in vitro. This enzyme was more sensitive than gyrase to inhibition by typical fluoroquinolone antimicrobial agents such as ciprofloxacin or sparfloxacin, adding strong support to genetic studies which indicate that topoisomerase IV is the primary target of fluoroquinolones in S. aureus. The results obtained with ofloxacin suggest that this fluoroquinolone could also primarily target gyrase. No cleavable complex could be detected with S. aureus gyrase upon incubation with ciprofloxacin or sparfloxacin at concentrations which fully inhibit DNA supercoiling. This suggests that these drugs do not stabilize the open DNA-gyrase complex, at least under standard in vitro incubation conditions, but are more likely to interfere primarily with the DNA breakage step, contrary to what has been reported with E. coli gyrase. Both S. aureus gyrase-catalyzed DNA supercoiling and S. aureus topoisomerase IV-catalyzed decatenation were dramatically stimulated by potassium glutamate or aspartate (500- and 50-fold by 700 and 350 mM glutamate, respectively), whereas topoisomerase IV-dependent DNA relaxation was inhibited 3-fold by 350 mM glutamate. The relevance of the effect of dicarboxylic amino acids on the activities of type II topoisomerases is discussed with regard to the intracellular osmolite composition of S. aureus.

scholarly journals The pivot point arginines identified in the β-pinwheel structure of C-terminal domain from Salmonella Typhi DNA Gyrase A subunit

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ekta Sachdeva ◽  
Gurpreet Kaur ◽  
Pragya Tiwari ◽  
Deepali Gupta ◽  
Tej P. Singh ◽  
...  
Keyword(s):  
Dna Gyrase ◽  
Salmonella Typhi ◽  
Pivot Point ◽  
Terminal Domain ◽  
Gyrase A ◽  
A Subunit

scholarly journals Molecular Cloning of Apicoplast-Targeted Plasmodium falciparum DNA Gyrase Genes: Unique Intrinsic ATPase Activity and ATP-Independent Dimerization of PfGyrB Subunit

2007 ◽  
Vol 6 (3) ◽  
pp. 398-412 ◽  
Author(s):  
Mohd Ashraf Dar ◽  
Atul Sharma ◽  
Neelima Mondal ◽  
Suman Kumar Dhar
Keyword(s):  
Plasmodium Falciparum ◽  
Atpase Activity ◽  
Dna Cleavage ◽  
Functional Characterization ◽  
Dna Gyrase ◽  
Heptad Repeat ◽  
Malarial Parasite ◽  
Temperature Sensitive ◽  
Linear Pattern ◽  
Gyrase A

ABSTRACT DNA gyrase, a typical type II topoisomerase that can introduce negative supercoils in DNA, is essential for replication and transcription in prokaryotes. The apicomplexan parasite Plasmodium falciparum contains the genes for both gyrase A and gyrase B in its genome. Due to the large sizes of both proteins and the unusual codon usage of the highly AT-rich P. falciparum gyrA (PfgyrA) and PfgyrB genes, it has so far been impossible to characterize these proteins, which could be excellent drug targets. Here, we report the cloning, expression, and functional characterization of full-length PfGyrB and functional domains of PfGyrA. Unlike Escherichia coli GyrB, PfGyrB shows strong intrinsic ATPase activity and follows a linear pattern of ATP hydrolysis characteristic of dimer formation in the absence of ATP analogues. These unique features have not been reported for any known gyrase so far. The PfgyrB gene complemented the E. coli gyrase temperature-sensitive strain, and, together with the N-terminal domain of PfGyrA, it showed typical DNA cleavage activity. Furthermore, PfGyrA contains a unique leucine heptad repeat that might be responsible for dimerization. These results confirm the presence of DNA gyrase in eukaryotes and confer great potential for drug development and organelle DNA replication in the deadliest human malarial parasite, P. falciparum.

scholarly journals Mutation in the DNA Gyrase A Gene ofEscherichia coli That Expands the Quinolone Resistance-Determining Region

2001 ◽  
Vol 45 (8) ◽  
pp. 2378-2380 ◽  
Author(s):  
S. Marvin Friedman ◽  
Tao Lu ◽  
Karl Drlica
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Dna Gyrase ◽  
Ofescherichia Coli ◽  
Quinolone Resistance ◽  
Gyrase A

ABSTRACT In three Escherichia coli mutants, a change (Ala-51 to Val) in the gyrase A protein outside the standard quinolone resistance-determining region (QRDR) lowered the level of quinolone susceptibility more than changes at amino acids 67, 82, 84, and 106 did. Revision of the QRDR to include amino acid 51 is indicated.

Sign in / Sign up

Export Citation Format

Share Document