[1] ROYAL INST TECHNOL, DEPT BIOCHEM & BIOTECHNOL, KTH, S-10044 STOCKHOLM, SWEDEN
[2] HUDDINGE UNIV HOSP, KAROLINSKA INST, DEPT IMMUNOL MICROBIOL PATHOL & INFECT DIS, DIV CLIN BACTERIOL, S-14186 HUDDINGE, SWEDEN
[3] INT CTR DIARRHOEAL DIS RES, DHAKA, BANGLADESH