Download presentation
Presentation is loading. Please wait.
Published bySamuel Stanley Modified over 9 years ago
1
Lab 4 Goals and Objectives: ***Use wax pencils (China Marker): Sharpie will wash off with alcohol! Be sure to resuspend broth cultures completely! Exercise 15: Gram Stain: Each pair make 2 slides each mix and stain: 1. Staphylococcus aureus & Pseudomonas aeruginosa: two loops of each broth mixed 2. Bacillus subtilis & Escherichia coli: two loops of each broth mixed ***95% Ethanol for Gram Stain, Acid-alcohol for Acid Fast Stain!!! 2 loops each organism mixed together Wax Pencil Exercise 17: Acid Fast Staining Each pair make 2 slides with: Staphylococcus aureus (use 2-4 loops of broth on slide first) Mycobacterium smegmatis (slant, use needle, get tiny amount and mix into broth on slide very well: break up all clumps) ***Make all smears on slides first so they can dry before heat fixing!!! Split the work to save time but make sure everyone gets to see all slides!
2
Figure 15.2 Figure 15.1
3
Crystal Violet = Primary Stain: stains all cell walls purple Iodine = Mordant: combines with crystal violet to create large insoluble dark purple complex Alcohol = Decolorizer: solubilizes Gram negative outer membrane flushing iodine/crystal violet complex out of thin wall, thick Gram positive cells resist decolorization Safranin = Counterstain: stains cell walls pink (obscured by purple walls of Gram positive, but Gram negative, who had become colorless, now are pink)
4
Lab 4 Goals and Objectives: ***Use wax pencils (China Marker): Sharpie will wash off with alcohol! Be sure to resuspend broth cultures completely! Exercise 15: Gram Stain: Each pair make 2 slides each mix and stain: 1. Staphylococcus aureus & Pseudomonas aeruginosa: two loops of each broth mixed 2. Bacillus subtilis & Escherichia coli: two loops of each broth mixed ***95% Ethanol for Gram Stain, Acid-alcohol for Acid Fast Stain!!! 2 loops each organism mixed together Wax Pencil Exercise 17: Acid Fast Staining Each pair make 2 slides with: Staphylococcus aureus (use 2-4 loops of broth on slide first) Mycobacterium smegmatis (slant, use needle, get tiny amount and mix into broth on slide very well: break up all clumps) ***Make all smears on slides first so they can dry before heat fixing!!! Split the work to save time but make sure everyone gets to see all slides!
5
On Website
6
Figure 15.3 Gram Staining (until water runs clear) immediately!!!
8
Acid Fast Stain Figure 17.1 30sec
10
Lab 4 Goals and Objectives: ***Use wax pencils (China Marker): Sharpie will wash off with alcohol! Be sure to resuspend broth cultures completely! Exercise 15: Gram Stain: Each pair make 2 slides each mix and stain: 1. Staphylococcus aureus & Pseudomonas aeruginosa: two loops of each broth mixed 2. Bacillus subtilis & Escherichia coli: two loops of each broth mixed ***95% Ethanol for Gram Stain, Acid-alcohol for Acid Fast Stain!!! 2 loops each organism mixed together Wax Pencil Exercise 17: Acid Fast Staining Each pair make 2 slides with: Staphylococcus aureus (use 2-4 loops of broth on slide first) Mycobacterium smegmatis (slant, use needle, get tiny amount and mix into broth on slide very well: break up all clumps) ***Make all smears on slides first so they can dry before heat fixing!!! Split the work to save time but make sure everyone gets to see all slides!
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.