1. University of Pennsylvania; Department of Biology; Philadelphia; PA; 19104; USA
2. Department of Membrane Biochemistry; Max-Planck-Institute of Biochemistry; 82152; Martinsried; Germany
3. J. Craig Venter Institute; Rockville; MD; 20850; USA
4. Environmental Molecular Sciences Laboratory; Richland; WA; USA
5. Division of Biological Sciences; Pacific Northwest National Laboratory; Richland; WA; USA