Microbiology Lab (BIOL 2230) – Fall 2013 PREP SHEETS
WK
6
10/2
Topics
Gram Stain & Microscope Practice
Students will Gram stain one slide
containing TWO smears from slant:
E. coli and S. aureus plus ONE
smear from mixed broth (see below)
Orgs
Per Table: 18-24 hour cultures
Streaking Practice
Students will streak ONE plate
from broth mixture containing E.
coli and S. aureus.
Plate Count
E. coli (broth: 1/table) 2 mL
Standard Plate Count: Procedure (6-1 and 16)
Students will work in groups of 4.
Each student will plate one dilution.
Antimicrobial Susceptibility (7-2)
 S#1: E. coli
 S#2: P. aeruginosa
 S#3: S. aureus
 S#4: S. epidermidis
NA Slant: (for Gram Stain)
 S. aureus
 E. coli
N Broth: (for antimicrobial)
 P. aeruginosa (4 mL)
 S. aureus (4 mL)
 S. epidermidis (4 mL)
 E. coli (4 mL)
For Instructor:
N Broth: (for streaking)*
 E. coli (6 mL)
 S. aureus (6 mL)

(*Instructor will mix the two broth
cultures immediately prior to
beginning of lab.)
Media
Per Student:
1 NA plates (streak)
1 NA plate (antimicrobial)
Per TABLE of Students:
4 NA plates (plate count)
For Class Cultures
[2 NAS] x 6 tables GS
[1 NB] x 6 (2 mL each) PC
[4 NB] x 6 (4 mL each) AM
Instructor Cultures
2NB x 1 (6 mL each)
4 sets of antibiotic disks with
dispenser.
Equipment
Per Table: spinners
1 bottle immersion oil
2 packets lens paper
1 dropper bottle each:
 deionized water
 crystal violet
 Gram’s iodine
 95% EtOH
 safranin
2 water spray bottles
1 package bibulous paper
2 Bunsen burners
1 striker
1 Lysol spray bottle
1 beaker w/biohazard bag
Sterile swabs
10, 100, 1000 microliters pipettes
Flask of sterile saline per table 150mL
Micro tubes 5 per table
Bent glass rod in beaker alcohol 250 mL
Note: alcohol just covers rod.
Per Student:
1 microscope
1 box of slides
1 clothespin (slide holder)
1 staining tray
1 inoculating loop
1 inoculating needle (OF)
On Side Bench:
large beaker w/10% bleach (slide disposal)
autoclave tray (culture disposal)
slide warmer