Dong H. Kwon

Biography

My research interests have centered in pharmaceutical biotechnology focusing on the molecular details of drug susceptibility/resistance mechanisms, finding new drug targets (or a new drug), and novel strategies to treat drug resistant (and susceptible) bacterial human pathogens. My researches have been supported by National Institutes of Health (NIH). I have been studying one of human pathogens Helicobacter pylori (H. pylori), which is a Gram-negative bacterium infecting more than 50% of the human population. H. pylori infection is etiologically associated with peptic ulcer disease, gastric lymphoma, and gastric cancer. Cure of the infection cures peptic ulcer disease and if done early in the course of the infection will prevent development of the H. pylori-related diseases including gastric cancer. While H. pylori is susceptible to most common antibiotics in vitro, clinically cure of the infection has proven difficult. Current H. pylori eradication therapies consist of combinations of two or more antibiotics including amoxicillin, clarithromycin, metronidazole, or tetracycline and antisecretory drugs. Overall, the cure rate in clinical practice has been in the range of 60 to 80%. Failure of treatment is most frequently due to the presence of antibiotic resistant H. pylori, and acquired-resistance to amoxicillin, clarithromycin, metronidazole, and tetracycline. Initial studies were focused on the resistance mechanisms in relation to amoxicillin, clarithromycin, metronidazole, and tetracycline. My work was devoted to understanding the molecular details of resistance to these antibiotics. The molecular bases of resistance to these antibiotics relate to chromosomal mutations on the antibiotic-target genes, (e.g., a gene encoding penicillin-binding protein [pbp-1A] for amoxicillin, genes encoding 23S rRNA for clarithromycin, genes encoding 16S rRNA for tetracycline, and inactivation of a gene encoding metronidazole nitroreductase [rdxA] for metronidazole). My studies have moved on finding new drug targets (or a new drug) and a novel strategy to treat the drug resistant (or susceptible) pathogens, in addition to H. pylori, including Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa, which cause a variety of hospital-acquired human diseases.

Research Interest

Molecular Genetics of Microorganisms; Antimicrobial Susceptibility/Resistance; Biochemistry