Technologies + Future Outlook Microbiology

Since we have started to harness the amazing power of bacteria, the field of microbiology has become much more prominent As we previously learned, we are developing new ways to utilize bacteria to our advantage! –Detergents –Mining –Textiles –Food Microbiology

Most bacterial cultures are processed much like we did in this lab –Swab “infected” areas –Culture bacteria on growth media –Observe colonies –Perform culture tests* –Oxidase, indole* –Perform gram staining procedure –Identify organism –Perform Antibiotic susceptibility testing In the clinical lab

However, a clinical lab has access to more $$, and are designed to be more microbiology specific than our lab. These are some of the interesting technologies used in clinical labs around the world today! Microbiology Technologies

Automated Laboratories

Clinical labs now have access to a wide variety of Chromogenic Media – The chromogenic mixture contains chromogenic substrates as Salmon-GAL, X-Gal, X-glucuronide, etc. – Certain enzymes, produced by some bacteria, cleave these substrates, resulting in the different coloration of certain bacteria colonies. Culturing Bacteria

Chromogenic Agar Automated Identification systems –E.g. the Vitek system (bioMerieux) –Bacterial cultures are inserted into cards with a variety of different compounds, which when metabolized, will let the user know exactly what organism you are dealing with Bacterial Identification

MALDI-TOF system –Matrix Assisted Laser dissociated/ionized – Time of Flight –Essentially, a machine which zaps bacteria with a laser, causing all the proteins and cellular components of that bacteria to travel up a tube. –Mass spectrometer – complex machine which measures the mass of particles, and tells exactly what the bacteria is, in a matter of 2 minutes –Typically takes 4-5 days to confirm positive results Bacterial Identification

First let’s look at a few key terms –Antibiotic –An antimicrobial agent, used to combat bacterial infections –Antiseptic –Antimicrobial agent applied to the surface of living tissue –Disinfectant –Antimicrobial agent that is applied to non-living surfaces for sterilization Antibiotic Susceptibility Testing

Bacteriocidal –Kills bacteria Bacteriostatic –Stops bacteria from replicating, long enough so host immune system can fight off infection Antibiotic Susceptibility Testing

Automated Systems –The Vitek system, which we previously learned about can be used to give an antibacterial susceptibility background to a wide variety of organisms Diffusion Systems –Etests –Kirby Bauer Disk Diffusion tests Antibiotic Susceptibility Testing

A strip of specialized paper, containing different concentrations of a specific antibiotic. Where the bacteria stops growing tells the doctor what dose of antibiotic to give that patient (MIC – minimum inhibitory concentration) Etests

Works by placing antibiotic disk on a cultured agar plate, and measuring the “zone of inhibition” size Tells whether the bacteria is sensitive or resistant to the antibiotic, depending on the zone size Kirby Bauer Disk Diffusion Test

By now, hopefully we realize the importance of bacteria in our everyday lives… good or bad. With a greater understanding of microbiology, more career opportunities open up into this exploration as well! So why is the study of microbiology important?

Clinical Physician –Immunologist –Microbiologist –Pathologist Laboratory Technician Food & Drink –Any major food company hires microbiologists –Same with any brewing company as well… –Wine microbiology Industry –Green movement in the 21 st Century has opened the door to many microbial practices –Biomining, bioremediation, biofuels Careers in Microbiology

Use Kirby Bauer Disc diffusion sheet in front of you, to determine “your bacterias” zone of inhibition sizes to different types of antibiotics –Which antibiotic would you use to combat this infection? NB. This is the hypothetical activity to replace the actual antibiotic test… it is possible these agents do not work against the organism you have found. –You must find your organism by deducing your Gram stain results + colony descriptions –Subsequently, determine which antibiotics are effective against that organism To Do Now

Continue to work on your Lab assignment, or continue review of Chapter 24. When you have finished