Mitochondrial protein help

[Arthur LaMarche]

Hi,

I am a graduate student working in the laboratory of Dr. Bernard Trumpower
at Dartmouth Medical School.  I study cytochrome c oxidase in yeast.  I
have purified the oxidase using anion exchange chromatography.  The
preparation looks good on SDS PAGE, but I have one contaminating band
running about 74 kd. If anyone has ideas on what the band could be I would
love to hear from you. 

Best regards,

art