[1] UNIV UPPSALA, CTR BIOMED, DEPT MICROBIOL, S-75123 UPPSALA, SWEDEN
[2] SWEDISH UNIV AGR SCI, CTR BIOMED, DEPT BACTERIOL & EPIZOOTOL, S-75123 UPPSALA, SWEDEN
[3] UNIV ALABAMA, HOSP DIABET, DEPT BIOCHEM, CONNECT TISSUE LAB, BIRMINGHAM, AL 35294 USA
[4] ROYAL INST TECHNOL, DEPT BIOCHEM & BIOTECHNOL, S-10044 STOCKHOLM 70, SWEDEN