Possible Clues:

• E. ___
• E. follower
• Last half of a tiny food contaminant (with first half of, um, you know...)
• Letters after E?
• E. -- (bacteria)
• E. ___ bacteria
• E. __ bacteria
• E. — (bacterium)
• Last half of a tiny food contaminant (first half is, um, you know ...)
• E. -- (gut bacteria)