[1] Monash Univ, Prot Crystallog Unit, Dept Biochem & Mol Biol, Sch Biomed Sci, Clayton, Vic 3800, Australia
[2] Univ Sydney, Sch Mol & Microbial Biosci, Sydney, NSW 2006, Australia
[3] Univ Melbourne, Dept Biochem & Mol Biol, Parkville, Vic 3010, Australia
[4] Univ Melbourne, Dept Microbiol & Immunol, Parkville, Vic 3010, Australia