Why can some organisms grow in the presence of oxygen? Toxic forms of oxygen need to be neutralized by enzymes Superoxide dismutase Catalase Peroxidase If microbe does not produce these enzymes must have anaerobic conditions Obligate aerobe Facultative Obligate anaerobe Microaerophiles Aerotolerant Bacteria Bacteria Enzymes in Cells for O2 Detoxification Catalase: 2H2O2->2H20+o Catalase Neither catalase Small amounts uperoxide dismutase Superoxide dismutase superoxide nor superoxide of catalase and dismutase dismutase in most superoxide dismutase 2O2+2H→ Source: Brooks GF, Carroll KC, Butel JS, Morse SA, Mietzner TA: Jawetz, Melnick, Adelberg's Medical Microbiology, 26th Edition: www, accessmedicine com Copyright o The McGraw-Hill Companies, Inc. All rights reserved.Why can some organisms grow in the presence of oxygen? Toxic forms of oxygen need to be neutralized by enzymes -Superoxide dismutase -Catalase -Peroxidase If microbe does not produce these enzymes must have anaerobic conditions