Microbiology
ASM Laboratory Skills and Competencies
1. Prepare and view specimens for examination using microscopy
a. Prepare a bacterial smear (using aseptic technique)
b. Fixation of cells (heat and alcohol)
c. Simple staining
d. Gram staining
e. Specialized stains (capsule, endospore, flagella)
f. Focus compound light microscope with 4x, 10x, 40x objectives
g. Adjust light and iris diaphragm
h. Focus under oil immersion (100x objective)
i. Care, cleaning and proper storage of microscope
2. Use pure culture and selective techniques to enrich for and isolate microorganisms
a. Basic aseptic technique
b. Transfer between media types (plate to broth, broth to slant etc…)
c. Streak for isolation
d. Choose media to aid selection and identification (EMB, MSA, PIA etc..)
3. Use Appropriate Methods to Identify Microorganisms (media, molecular, serological)
a. Choose and interpret results of growth on Differential and Selective Media
b. Biochemical/Metabolic assays, knowledge of reagents and products, and
interpretation of test results
c. ss-rRNA/DNA hybridization/G-C ratio concepts and results interpretation
d. Molecular lab techniques (?)
4. Estimate the number of microorganisms in a Sample
a. Direct cell count - Microscopy/counting slides- viable cell stains
b. Viable Plate count: create dilutions, prepare spread plates and pour plates, then
analyze results and calculate CFU/ml
c. Serial dilutions and pipetting
d. Spectrophotometry (OD readings) Create and use a standard curve to estimate
cell number
5. Use Appropriate microbiological and molecular lab Equipment and Methods
a. Volumetric tools: graduated cylinders, serological pipettes, micropipettes
b. Transfer tools: Inoculating loops, Inoculating needles, swabs, pipettes
c. Sterilization tools: Burners, Autoclave, use and safety
d. Set temperature of incubators
e. Plasmid transformation
f. Employ Koch’s postulates to isolate and identify pathogen (simulated: yogurt)
g. Other?
6. Practice Safe Microbiology using appropriate protective and emergency procedures
a. Wearing proper PPE for the lab, situation, and organism
b. Aseptic Technique and disposal of biohazardous waste
c. General lab safety practices