BIMM 121 Microbiology Lab Notes

Topics

  • What's coming up?
  • Introduction to biofilm/microcosm project
  • Experimental design

What’s coming up – Math

  • WHY math quizzes?????? We will be using math in the lab, starting tomorrow!
  • When is the next math quiz?

What's coming up - Math

  • How can I improve???
    • Week 2 Module
    • Material for lab on Wed, Apr 9
    • Material for lab on Fri, Apr 11
    • Second set of practice dilution problems

What's coming up - Math

  • How can I improve???
    • Week 3 Module
    • Material for lab on Wed, Apr 16
    • Materials for lab on Fri, Apr 18
    • Third set of practice math problems

What's coming up - Math

  • How can I improve???
    • Math and dilutions
    • Understanding Dilutions
    • Guidelines for dilutions
    • Dilution Practice problems 1
    • Dilution Practice solutions 1
    • Video tutorial (50 minutes) on how to do lab math in BIMM 121:

What's coming up - tomorrow

  • The following points were shared:
    • Wed, Apr 9
    • QUIZ on three microscopy videos; MATH QUIZ 1
    • Examine liquid cultures from A2
    • Examine T-streak plate from A3
    • SAVE one streak plate per bench for use in next lab
    • BASICS2 - MICROSCOPY with prepared slides; use brightfield
    • Fri, Apr 11 MATH QUIZ 2
    • B1 set up microcosms for biofilm evolution
    • MICROSCOPY - wet mount & phase contrast optics (yeast; Pseudomonas saved from A3, throw away at end of lab)
    • You will find a plate of yeast on your bench, for microscopy.

What's coming up - Week 3

  • Topic highlighted were:
    • Prep for Weds lab, draw out a diagram and/or table of how you will do your dilutions BEFORE
    • NO B3 experiment Next week is a heavy week.

What's coming up - Week 3

  • Topic highlighted were:
    -Week 3 Module
    -Material for lab on Wed, Apr 16
    -Materials for lab on Fri, Apr 18
    -Third set of practice math problems

What's coming up - Week 3

  • A research paper needs to be read for Wednesday.
    The paper is Nature 1998 paper.

Microcosms - Definition

  • Biofilm = consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances, according to Wikipedia

Microcosms - inoculations

  • To do experiments follow the below steps:
    -Use BEST aseptic technique!!!
    -SBW25 Pseudomonas fluorescens bacteria will be used and should be labeled with unique ID number from spreadsheet as follow:

Microcosms Aseptic technique checklist

  • The following information should remembered:
    -Sterilize workspace with ethanol;
    -Uncluttered workspace
    -Position Bunsen burner in center of bench
    -Adjust flame height Set up workspace according to dominant hand
    -Loosen caps before starting
    -flame tubes before AND after removing cells
    -Keep the tubes and materials sterile Transferred loop is only touched to inoculations.
    -Ensure you use sterile tools and sterilize them (flame) after used.
    -Complete transfer with graceful movements, be quick to not let materials get contaminated.
    -Make sure to sterilize loop after finished . Never give a lid or cap to someone else and Never set a lid or cap on the bench. Always Watch the aseptic technique video AGAIN before your next inoculation . Never switch hands while holding something.

Microcosms - overview

  • Show graphical representations of experiment. You should draw your own experiments like this.

Microcosms - Experimental design

  • Various conditions and components for setting up your lab are as follows: -vial condition additive amount of additive bacteria KB total volume -1 static 10 µL 6 mL 2 static 10 µL 6 mL 3 static 10 µL 6 mL 4 static 10 µL 6 mL 5 static none - 10 µL 5 mL + 990 µL 6 mL -6 static none - 10 µL 5 mL + 990 µL 6 mL shake a 7 none - 10 µL 5 mL + 990 µL 6 mL 8 shaking none - none 6 mL 6 mL
    • experimental vials: controls vials-duplicates.

Microcosms - Experiment B1

  • How do you determine a volume that is 2% of the total? Determine this volume in advance of lab!
  • If you use H2O2, do NOT exceed 1%.

Static microcosm No additive Shaken microcosm No additive

  • To perform experiment note below pointers:
    -WHAT do we want to learn?