a.Functions of Bacterial pigments
-it depends on the species
1. Photosynthetic bacteria: produce pigments such as chlorophyll which absorb sunlight in the process of photosynthesis
2. Nonphotosynthetic bacteria: make pigments:
a. as byproducts of their metabolism
b. as antioxidants
c. to eliminate toxic by-products
d. as protection against solar radiation
b. Source of Pigment
1. Some pigments are intracellular
2. others are extracellular and diffuse into their surrounding medium
ex. blue/green pigment produced by Pseudomonas aeruginosa
-it creates blue/green puss in wounds that contain it
c. Pigments are useful when identifying unknown bacteria
d. the expression of pigmentation can vary depending on environmental conditions, including:
1. type of medium
2. temperature
Colonies we look at:
#3 Bacillus globigii= the globe is brown/orange/tan
#9 Chromobacterium violaceum= has 2 violet (viol)
#24 Micrococcus luteus= yellow color
#25 Micrococcus roseus= 22*C has rose color, one clear
#33 Pseudomonas aeruginosa= 37*C has green tint
#39 Serratia marcescens= has one red one white
#45 Janthinobacterium lividum has one violet, one no growth
#3 Bacillus globigii= the globe is brown/orange/tan
#9 Chromobacterium violaceum= has 2 violet (viol)
#24 Micrococcus luteus= yellow color
#25 Micrococcus roseus= 22*C has rose color, one clear
#33 Pseudomonas aeruginosa= 37*C has green tint
notice green color
#39 Serratia marcescens= has one red one white
#45 Janthinobacterium lividum has one violet, one no growth
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