October 2017 Discover

12 DISCOVERMAGAZINE.COM

THE CRUX

CLOSE-UP

EVERYDAY COMPANIONS

Bacteria are everywhere we are. Tasha Sturm, a lab technician at Cabrillo College in Aptos, Calif., has been swabbing common objects for 14 years,

culturing her discoveries and teaching the technique to students in fourth grade and up. Although she doesn’t have time to positively identify her

finds, she can sometimes eyeball it based on morphology, and she photographs the cultures in her free time. (A) This sample harvested from a shoe

sole is either yeast or Bacillus, a genus of bacteria with members that can cause anthrax or food poisoning. (B) Yeast from a lab table overtake

smaller colonies. (C) These potential bacilli came from a backpack and (D) an unwashed fingertip. After a few days to a month, these samples grew

to be dime-sized except the fingertip sample, which is pea-sized.  ERNIE MASTROIANNI; PHOTOS BY TASHA STURM/CABRILLO COLLEGE/MICROBEWORLD

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