Table 1 Polymerase chain reaction primers used in this study

HA1-2-F1

5′-CCCGAGCTCAAAGGGAAAAGGACAGTTGACC-3′

SacI

HA1-2-R1

5′-CCCAAGCTTGGCATCAACCTGTACT-3′

Hind III

HA1-2-F2

5′-CCGGAATTCAAAGGGAAAAGGACAGTTGACC-3′

EcoRI

HA1-2-R2

5′-CACCTCCGCTTCCACCTCCACCGGCATCAACCTGTACT-3′

(Gly₄Ser)₃

fliC-F

5′-AGGTGGAAGCGGAGGTGGTGGAAGCATGGCACAAGT CATTAATA-3′

(Gly₄Ser)₃

fliC-R

5′-CCGTCTAGATTAACGCAGTAAAGAGAGGACG-3′

XbaI