The suspension was incubated at 50 1C for 10 min, centrifuged for 30 s and the pellet was washed twice with buffer QxI
and one time with buffer PE. After air-drying for 15 min, the DNA was eluted with nuclease free water. DNA cycle sequencing was done with the ABI Prism BigDye terminator kit (Perkin-Elmer Applied Biosystems, Foster City, CA) and an Applied Biosystems ABI 3100 genetic analyzer.