vaccination with either chloroform-methanol-extracted cell residues of c. burnetii or the 27-kilodalton major surface protein evoked an early igg2 response to the 27-kilodalton protein ( 2 weeks after immunization ) , whereas igg2 to lipopolysaccharides of c. burnetii was detected only in the late phase ( 13 weeks after immunization ) .
C0025252
surface protein
C0033684
protein