Question

In the IMViC tests explain:

1) How does tryptophanase cause the tube to turn red? Explain the chemical reactions that occur.

2) How and why does the productionof hydrogen sulfide cause the tube to turn black? Explain the chemical reactions that occur.

3) In the MR-VP test, how does mixed acid fermentation cause the tube to turn red and how does acetoin cause the tube to turn red in the VP test? Explain the chemical reactions for each.

Answer 1

Hello, we are a Solution, Today to discuss about going murobiology related questions : o muc test és a most widely used test to the unknown bacteria imuro test encludes a group individual tests • Imvu test includes mdole production test, Methyl sed test, Voges-Proskauer test and citrate production of tast.

we can production test, find the 1) in the indole Red colour • Some bacteria produce tryptophanase enzyme. This enzyme helps to catalyze the deamination from tryptophan - o the tryptophan is converted into mdole. And the Kovais with indole to reagent combines produ lue

Red colour. • kova's reagent certain Hb, p methylamuno benzaldehyde, amyl alcohol ete. This helps media from yellow to red. cato chemical reaction o the brystophase atalynes the conversion of tryptophan to indole. Deamination of tryptophan results in the production of Indole andole combines with kovais Red colour. That's in indole positive tabe find red color. of seagent to produce why in ule lan

The by amuno and. because that produced by we can find black color in Hydrogen sulfide gas is produced the breakdown of sulfur containing The tube turns black, the hydrogen sulfur the reduction of sulfur will combine with low Salts (Feat) and form • Ferric susfide. The ferric sulfide is in black color. That's why the test tube that contain Hydrogen Sulfide. chemical reaction of this test, the contain amino aids sulfur lining are included in the medium. bauteria uses containing o the Sulfur in the aminoaud get reduced The sufur reduring the sulfur 0 amino and

as end and produce has e hydrogen sullide produt'. hydrogen sulfide o this acto detention we is colourless. So for use Ferric salts iu kon salts Feat. On reaction with Iron salts formation of of Ferrio Sulfide Hydrogen sulfide will results in the in the tube "Because of Ferric selfide production find black color. we can of

3) Methyl Red and Noges - Prostrauer fermentation. The oh red test is used. The MR-up lest is Methyl test . OMR test includes mixed and gluose is fermented and of it produce more auds then the medium will change to red. & methyl gluose fermentation will of gluose results in the auds production of when & enters to mixed and pathway. high concentration aids will results in the decrease in pH and the media become audic. audic PH) the colour because of methyl red inducator. These of Because to red of changes

presence of autoin. presence of of up lest is Voges Prostrauer test. And it is mainly to detail the The auto in causes red color because with the reaction Pottassium and hydroxide a-haphthol. Positive results will show red colour. The get fermented by bacteria. And the Pyrétrico and to butylene glycol pathway. glucose rose in the medium formed is enter stoint

q This results in the formation autoin otretain combines with Poltassium hydros roxide and form diautyl reaction with a thol results in the Me test shows red colours because of this diacetyl on a-haghth red colour formation of Methyl red indicator And positive up test shows red colour because of koll and a-naphthol Thank you .

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