A colleague of yours has produced a set of meda that was noculated wth the same

Question

A colleague of yours has produced a set of meda that was noculated wth the same badera. But due to poor labeling technique, they need hep n soMng the mystery. You have a kind nature so have offered to hep out this hapless coleague. Interpret the resut for each meda (the results listed are comect, aan betrusted, and nothing went wrong with the inoculation) wth the help of the Gram tables at the end of unt 13 n your lab manual, determine the organism's identty. Use the following abbreviations for the eliminated organisms in each case. atrobacterfreundi- Cf, Bschenbha col- Ec, Kebsela pneumonae- Kp, Poteus vugars-Pv Pseudomonas aeruginosa Pa, Serrata marcescens-Sm, Shgel fexneri- Sf You must gMe acomplete descrpton of what the test resuts telyou and why!! This means you will need to note what you know about products, pH enzymes present etc for full credt Notice that in each case you must tell me which bacteria the results eliminate for that test only. That means you say "f these resuts are accurate then this organism should not be Consider carefully the catabolism information and dearly interpret allresuts. Answers that simply state negatMe or postMe wthout nterpretation of the resuts will not be considered. Be specfic. Please turn a neat and professional looking quiz. 1. You locate the TSI tube and see the following the slant is pink and the butt is yellow, there are no bubbles in the butt on of the agar and the stab looks good. Result: AA KK, AK, KIA (cicle one) pH indicator present: Interpretation (be complete explain both the slant and the butt, including enzymes): Slant: Butt: This test elminates (crcle elminated s Cf /Ec /Kp /Pv /Pa /sm/sf

Explanation / Answer

1. K/A

slant- when lactose is not fermented,but glucose is,the less acd produced will be oxidized to carbon dioxide and water

butt- lactose is not fermented but glucose is,the acis produced turns phenol red indicator yellow, the oxygen deficient butt will be yellow

this test eliminates Ec

2. MR test -positive VP test- negative

reagent for MR test - methl red(p- dimethylaminoaeobenxene-O- carboxylic acid)

reagent for VP test- alha naphthol and potassium hydroxide

interpretation- the MR test is used to determine whether the organism does mixed acid fermentation.The large amount of acid decreases the pH of the medium,which is detected by methyl red indicator which is red at pH 4.4.

VP test-This test is used to detect the presence of acetoin in bacteria.On addition of VP reagent ,a cherry red colour ring indicates a positive test.

MR test eliminates Ec

VP test eliminates Kp

4. pH indicator of macconkey media- neutral red

interpretation- clear colonies are formed by nonlactose fermenting bacteria,which do not utilize lactose instead use peptone.This forms ammonia,raises the pH and leads to formation of colourless colonies.

this test eliminates -Ec,Kp

5.interpretation

sulphur- no blackening indiactes no H2S production.

indole- negative indole test .It means that the organism does not produce the enzyme tryptophanase that degrades tryptophan to produce indole

Motility- no motility,because there is no cloudiness along the stab line.

This test eliminates Kp

6. indicator-phenol red

interpretation- yellow colour with growth indicates that the organism does not produce the enzyme urease that splits urea into ammonia and carbon dioxide.

This test eliminates Ec

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