Lab 8: Pigments of Bacteria

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

Lab 7: Colony Morphology

***note: the spacing on this post is really weird and I don't know how to fix it, sorry****

Lab7: Colony Morphology

a. Colony= closely associated group of bacteria formed from the binary fission  (dividing) of a single bacteria 

-diving of single bacteria (binary fission) occurs on agar plate

- a colony is easily visible once there are over a million bacteria present

b. Colony Morphology= is the form (or look) of a colony that an individual  bacteria grows into on an agar plate 

* recognizing colony morphology is helpful when:

1. distinguishing bw mixed bacterial cultures and 

2 for identifying unknown bacteria 

*note that the colony characteristics such as size and pigmentation can vary depending on environmental conditions, including medium and temperature

We are looking at Bacteria:  (we look at each at 22*C and 37*C) 

#3: Bacillus globigii= the globe is brown/orange/tan color (more pronounced on 22*C)

#4 Bacillus licheniformis= both colonies are raised, 37*C looks like big wad of snot OR like lichens that grow on rocks 

#5 Bacillus megaterium= cirular

#6 Bacillus mycoides = 22*C looks like roots from MY garden 

#3: Bacillus globigii= the globe is brown/orange/tan color (more pronounced on 22*C)

 Bacillus globigii  

22*C

 Bacillus globigii  37*C

#4 Bacillus licheniformis= both colonies are raised, 37*C looks like big wad of snot OR like lichens that grow on rocks 

 Bacillus licheniformis 22*C 

 Bacillus licheniformis 37*C

 tree lichen : )

#5 Bacillus megaterium= circular

Bacillus megaterium 22*C

Bacillus megaterium 37*C

#6 Bacillus mycoides = 22*C looks like roots from MY garden 

Bacillus mycoides 22*C

Bacillus mycoides 37*C