微生物學及臨床微生物學（包括細菌與黴菌）題庫下載題庫

Phenylalanine Deaminase Test

Phenylalanine deaminase medium tests the ability of an organism to produce the enzyme deaminase. This enzyme removes the amine group from the amino acid phenylalanine and releases the amine group as free ammonia.  As a result of this reaction, phenylpyruvic acid is also produced.

Phenylalanine agar, also known as phenylalanine deaminase medium, contains nutrients and DL-phenylalanine.  It is used to differentiate members of the genera Proteus, Morganella (which were originally classified under the genus Proteus), and Providencia from other Enterobacteriaceae.

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Phenylalanine Deaminase Test

Phenylalanine deaminase medium tests the ability of an organism to produce the enzyme deaminase. This enzyme removes the amine group from the amino acid phenylalanine and releases the amine group as free ammonia.  As a result of this reaction, phenylpyruvic acid is also produced.

Phenylalanine agar, also known as phenylalanine deaminase medium, contains nutrients and DL-phenylalanine.  It is used to differentiate members of the genera Proteus, Morganella (which were originally classified under the genus Proteus), and Providencia from other Enterobacteriaceae.

After incubation, 10% ferric chloride is added to the media; if phenylpyruvic acid was produced, it will react with the ferric chloride and turn dark green.  If the medium remains a straw color, the organism is negative for phenylalanine deaminase production.

總結:如果細菌有phenylalanine deaminase，會產生phenylpyruvic acid。phenylpyruvic acid會跟ferric chloride反應而呈現深綠色。如果培養基還是維持稻草色，那待測細菌應該為phenylalanine deaminase (-)

陽性菌:Proteus spp. ,Morganella ,Providencia spp. 

https://www.austincc.edu/microbugz/phenylalanine_deaminase_test.php