Wastewater Microbiology Blogiology

Lab 4:  Using the Spectrophotometer to Measure the Rate of Bacterial Cell Division: A Bacterial Population Growth Curve (Photo:Miamioh) Introduction     The purpose of this lab will ultimately be to observe the growth of an Escherichia coli population in its lag phase, its exponential growth phase and its stationary phase.  Each group will measure the turbidity of different E. coli samples all taken at different times to get a wide range of measurements that will then construct a growth graph.  The biggest issue will most likely be the counting of the hemocytometerns that contain the E. coli .     While it is different for every bacteria, E. coli has a doubling time as short as 20 minutes. However, once they are placed in a growth medium (in this case LB broth), they will take some getting used to their environment. This period of adjustment is called the lag phase and will seen as the initial flatline on the growth curve graph.  Once th...

Lab 3: Streak Plate, Culture Transfer Instruments and Techniques, Isolation and Maintenance of Pure Culture (Photo: Pinterest) Introduction     The purpose of this lab will ultimately be to grow a pure culture of  Escherichia coli, place a colony inside LB broth and freeze a stock all to be used in later labs.  However, this will be complicated by the fact that microorganisms do not grow in neat, pure populations.  A pure culture must be isolated first from a mixed community.  The first of such ways would be to grow a sample onto selective media so that the media's components only allow the growth of limited or one type of microorganisms. ( A selective media is a specialized concoction of specific elements that provide for the growth and success of limited microorganisms.  The list of ingredients of selective media differs from non-selective media in that it is much longer and more complex. )  After  this is done, a single, specifi...

Title: Advanced biofuel production in microbes 1. What is the study’s objective/hypothesis/question? The study looked in to the recent developments relating to the production of biofuels by microorganisms. The metabolic engineering of Escherichia coli and Saccharomyces cerevisiae , both easy to control, were the two organisms whose genetic and regulatory processes were monitored for the production of such biofuels. 2. What is the rationale and relevance of the question? (i.e. why was the study done?) This study was conducted as a response to the innovation following the US Energy Independence and Security Act of 2007 that called for the production of 36 billion gallons of renewable fuel by 2022.   While ethanol produced from starch is a strong forerunner in these developments, ethanol is corrosive and draws too much moisture from its surroundings to be an economically feasible primary fuel of the future.   Ethanol also only contains 70% of the energy content of gaso...

Lab 2: Media Prep and Autoclave, Plate Pouring (Photo: Chester) Introduction     The purpose of this lab will ultimately be to prepare and pour plates of two different medias in preparation for later labs.  Pouring the appropriate amount of media into each petri dish will be the biggest issue and it is predicted that the technique will get better as more plates are poured.     While there are many different types of media used in microbiology labs, one of the most common is Luria-Bertani (LB).  Due to its richness in nutrients, it provides good food for bacteria and is simple to make. In addition to its prime conditions for a pure culture, it provides enough food so a culture may grow quickly.     While LB is typically used to grow Escherichia coli , it is a common media in every lab.  The most common recipe is: combine 10g of tryptone, 5 g of yeast extract, 10 g of NaCl and 1 liter of distilled water; adjust the pH to 7.0 with 1 N Na...

Lab 1: Working with a Pipette (Photo: Ralo) Introduction     As more classes become integrated with laboratory techniques, the proper handling and care of different materials is crucial to such success.  The objective of this lab was to learn how to correctly and accurately use micropipettors to measure small volumes of liquid.     The FGCU lab is equipped with the Eppendorf pipettes, particularly the 10-100 μL (yellow pipette) and the 100-1000 μL (blue pipette) versions.  Any measurement above or below the defined range (listed on the top of the device) does not guarantee accuracy.  By twisting the grooved wheel on top of the pipette, the desired measurement can be increased or decreased and read on the side of the device.  Each pipette is to be used with a particular disposable tip in the sanitized plastic racks: yellow tip=yellow (100) pipette, blue tip=blue (1000) pipette.  Tips are attached by opening the plastic ra...