2004 Research Fair Archive - Biology Abstracts
DNA Repair and Photoprotection in Halophilic Archaea
Halophilic Archaea are much more resistant to ultraviolet (UV) light damage than Escherichia coli and other species of Bacteria. Extreme halophilic organisms use light-driven ion pumps to maintain an acceptable internal environment despite living in water that has salt concentrations up to 30%. This need for light requires that the organisms experience more UV exposure than most other known microorganisms. For this reason, they have developed survival mechanisms, including efficient DNA repair processes. We propose that halophilic Archaea also employ photoprotective mechanisms such as low adenine-thymine ratios to avoid thymine dimers and pigmentation to protect from UV damage. Rupp, Allred, and Baxter examined several strains, including Halobacteria NRC-1 and an unidentified isolate from the Cargill salterns near Great Salt Lake, Utah.
Genetic and Clinical Characteristics of 103 Patients With Primary Pulmonary Hypertension
Mutations in the gene that codes for bone morphogenetic protein receptor two (BMPR2) are present in many patients with primary pulmonary hypertension (PPH). The purpose of this study is to identify novel mutations in BMPR2 and report clinical characteristics of PPH patients heterozygous for mutations in BMPR2. Glissmeyer uses high-resolution melting curve analysis and subsequent gene sequencingto scan the BMPR2 gene of 103 patients affected by either sporadic or familial PPH. He found seven novel BMPR2 mutations exist in this cohort of 112 PPH patients. The severity of disease observed in patients with PPH does not appear to be affected by the presence of mutations in BMPR2; however, such mutations do appear to affect the likelihood of vasoreactivity in the PPH patient.