TABLE 2.

PCR primers used in this study

Primer	Nucleotide sequencea
Y1	5′-CGGAATTCCTTACACATGGGTGACAAACGCAGTG-3′
Y2	5′-CGGATCCACGTATCATCACCGATCAGATTGCC-3′
pbpy-5′	5′-CATATGAAAAAAAGCATAAAGCTTTATG-3′
pbpy-3′	5′-GGATCCCTATTATTGATTTGCCAAAATG-3′
pbpy-P5	5′-CATATGGCTGAAAAACAAGATGCACTTTC-3′
pbpy-P6	5′-GGATCCCTAATTTAGAAGAATAGAGAAAACAAG-3′
yoxa-P2a	5′-CGCGGATCCTTGATTCATTGCTAG-3′
yoea-3′	5′-TCCCCCGGGTGCCTGTCGCTTTC-3′

^aRestriction endonuclease sites are underlined.