Gram Negative Rods E. coli P. vulgaris P. fluorescens C. freundii E. aerogenes K.pneumoniae A. viscolactis S. marcescens Gram Negative Cocci M. catarrhalis N. sicca
Oxidase
+ + -
Methyl Red
+ + + + + +
VP
+ +
+
+=color change within 30 sec -=no color change or after 30 sec
+=red, weak O -=yellow
+=red layer at top in 10 min -=no red color