DNA helicases in higher plants;

MCM2～7 proteins are related to each other and form hexamer,functioning in the replication as DNA helicases at the initiation step and elongation step,to ensure the DNA precisely duplicated and segregated into two copies.

PDH45 is a DNA helicase from pea, which has been proved to be able to largely enhance the salt tolerance of transgenic tobacoo.

Fluoroquinolone resistance and DNA gyrase mutations in Salmonella Isolated from Chickens;

OBJECTIVE To study the differences of quinolones-resistant determining region(QRDR) in DNA gyrase A(gyrA) subunit between drug-resistant Klebsiella pneumoniae induced by fluoroquinolone in vitro and strains isolated from clinical isolates.

To study the relation between alterations in DNA gyrase subunit A (GyrA) and fluoroquinolone resistance in Klebsiella pneumoniae .

Study and primary application of the screening model for antituberculosis drugs with DNA gyrase B subunit as a target;

To perform a systematic analysis of point mutations in the quinolone resistance determining regions(QRDRs)of the DNA gyrase and topoisomerase genes of Streptococcus suis type 2 strain after in vitro exposure to stepwise increasing concentrations of enrofloxacin and ciprofloxacin.