diff mediasv
DESCRIPTION
differential mediaTRANSCRIPT
![Page 1: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/1.jpg)
• Labs #6 (whitewhite) and #7 (green)• Overall scheme: Lab #6 (whitewhite) , last page
Biochemical Tests and Diagnostic Media
![Page 2: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/2.jpg)
SIM medium: Motility test
POSITIVE:Organism moves away from stab
NEGATIVE:Organism does NOT move away from stab
![Page 3: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/3.jpg)
SIM medium: Sulfur test
H2S-POSITIVE:black precipitate
formed
H2S-NEGATIVE:no black
precipitate formed
![Page 4: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/4.jpg)
Simmon’s citrate agar slant
positivenegative
![Page 5: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/5.jpg)
Diagnostic Media
• Mannitol salt agar• Eosin methylene blue (EMB) agar• Brilliant green agar
![Page 6: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/6.jpg)
Selective medium
Selects for the GROWTH of some organisms and inhibits the growth of
other organisms.
i.e. Some organisms grow on a selective medium whereas others do not grow (or do not grow well) on that
same medium.
![Page 7: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/7.jpg)
Differential medium
Differentiates between one type of organism and another type of organism.
Different types of organism look different from each other when grown on differential media.
![Page 8: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/8.jpg)
Mannitol salt agar
Selective mediumHigh salt (NaCl) concentration in medium favors organisms that tolerate high salt concentration, e.g. Staphylococcus.
Staphylococcus aureusgrows
Serratia marcescens
does not grow
![Page 9: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/9.jpg)
Mannitol salt agar
Differential medium
Differentiates among staphylococci
![Page 10: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/10.jpg)
Mannitol salt agar
Differential medium
Differentiates among staphylococci
![Page 11: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/11.jpg)
Mannitol salt agar
Differential medium Differentiates among staphylococci:• pathogenic Staphylococcus species ferment mannitol to produce acid (yellow medium)(yellow medium)
Staphylococcus ferments mannitol(yellow)(yellow)
![Page 12: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/12.jpg)
Mannitol salt agar
Differential medium Differentiates among staphylococci:• pathogenic Staphylococcus species ferment mannitol to produce acid (yellow medium)(yellow medium)• less pathogenic Micrococcus (a staphylococcus) do not ferment mannitol (red/pink medium)
Staphylococcus ferments mannitol(yellow)(yellow)
Micrococcus does not ferment mannitol
(pink)
![Page 13: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/13.jpg)
Levine Eosin-Methylene Blue (EMB) Agar
Gram negatives (growth)
Gram positive(growth inhibited)
SELECTIVE MEDIUM
![Page 14: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/14.jpg)
Levine Eosin-Methylene Blue (EMB) Agar
Nonlactose fermenters
Lactose fermenter
DIFFERENTIAL MEDIUM
![Page 15: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/15.jpg)
High acid producers on EMBe.g. E. coli
blue-black colonies or metallic sheen
![Page 16: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/16.jpg)
Levine Eosin-Methylene Blue (EMB) Agar
Lactose fermenter (low acid producer:
pink colonies)
Non-lactose fermenter Lactose fermenter (high acid producer:
black colonies)
Gram positive(growth inhibited)
![Page 17: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/17.jpg)
Brilliant Green Agar
SELECTIVE
DIFFERENTIAL
• Growth of all gram positive and many gram negative bacteria inhibited
• Growth of many Salmonella species occurs
![Page 18: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/18.jpg)
Brilliant Green AgarDIFFERENTIAL
Differentiates lactose fermenters lactose fermenters from nonlactose fermenters
![Page 19: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/19.jpg)
Brilliant Green AgarNon-lactose fermenter Lactose fermenter
SalmonellaE. coliE. coli
![Page 20: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/20.jpg)
Catalase Test
Many bacteria produce the enzyme catalase.
H2O2 H2O + O2catalase
hydrogenperoxide
oxygen (gas)
![Page 21: Diff mediasv](https://reader033.vdocuments.site/reader033/viewer/2022061505/557d1d71d8b42a6e4f8b4d9a/html5/thumbnails/21.jpg)
Catalase Test
bubbles (gas)
Catalase positive organism