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Title 21

Displaying title 21, up to date as of 6/04/2026. Title 21 was last amended 6/03/2026.
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§ 173.170 Aminoglycoside 3′-phosphotransferase II.

The food additive aminoglycoside 3′-phosphotransferase II may be safely used in the development of genetically modified cotton, oilseed rape, and tomatoes in accordance with the following prescribed conditions:

(a) The food additive is the enzyme aminoglycoside 3′-phosphotransferase II (CAS Reg. No. 58943-39-8) which catalyzes the phosphorylation of certain aminoglycoside antibiotics, including kanamycin, neomycin, and gentamicin.

(b) Aminoglycoside 3′-phosphotransferase II is encoded by the kanr gene originally isolated from transposon Tn5 of the bacterium Escherichia coli.

(c) The level of the additive does not exceed the amount reasonably required for selection of plant cells carrying the kanr gene along with the genetic material of interest.

[59 FR 26711, May 23, 1994]