FIELD T-2 

 Columns 58, 59, 60, and 61 



of the available Field T- 1 symbols can be used to indicate that the action of the enzyme in Field T-2 

 represents the alteration of the test compound. The original philosophy may be supposed to have been 

 that a provision for coding the fact that a specific enzyme brought about a test compound's alteration 

 was unnecessary, because it is not the intent of the CBCC to code in vitro actions of one compound 

 (the enzyme) on another (the test compound); even though enzymes represent products (or even might be 

 considered as components) of living organisms, the fact that the demonstration of the enzyme action on 

 the test compound is nearly always in vitro contributed to the concept that the test compound's alteration 

 should not be coded, because the results can not necessarily be inferred to occur in the living organism 

 (i. e. , the alteration of the test compound by the enzyme in vitro can not be assumed to be an alteration 

 of which the test organism [source of the enzyme] is capable by its enzyme in vivo ). In connection with 

 this, it should be understood that the coding of alterations of test compounds (and secondary and tertiary 

 compounds) has been a more recent development in the CBCC Code; the information was not selected for 

 coding during the first years. This represents another factor contributing to the establishment of the 

 ruling not to code the test compound's alterations by specific, named enzymes. 



It is suggested, however, that this ruling be revised so that information on alteration of the test 

 compound by specific enzymes be coded when the enzyme is named. Without altering the procedure to 

 be used when the enzyme is coded in Field T-2 (i. e. , when the test compound affects a specific enzyme), 

 the enzyme action could be translated into one of the alterations designated by a symbol of the FE-- 

 series and the alteration coded accordingly. It would not seem necessary, if this procedure were 

 adopted, to make any special coding provision for indicating that it was an in vitro demonstration, since 

 this is generally the case with most demonstrations of alteration of the test compound as well as of 

 effects of the test compound on enzyme actions. 



When the test compound is demonstrated to affect a specific enzyme's alteration of a secondary 

 compound, the CBCC does not code Field T-2 with the alteration affected (a symbol of the FE-- series), 

 but always codes Field T-2 with the specific enzyme, coding Field T-l as indicated in Division 22 and 

 coding the secondary compound in Field D. 



Occasionally, information is encountered which describes a chemical as having been demon- 

 strated to be used by a biological system as the precursor for a specific chemical component or product 

 of the organism. This does not mean that it is incorporated per se into the final product and therefore 

 it should not be coded by use of Symbol FH--. Further, the fact that the test compound is actually 

 altered to another specified material does not make the process suitable for inclusion with those symbols 

 making up a series describing the metabolic fates of unaltered compounds (Symbols FG--, F8--, F9--, 

 FA--, FB--, FC--, FG--, FH--, andFI--), but more logically associated with symbol series FE-- 

 specifically concerned with alteration. The chemical reactions which involve this use of the precursor 

 to synthesize the final product are seldom described or known; therefore, specific symbols of the FE-- 

 series can most frequently not be used to describe the specific alteration of the precursor. The CBCC 

 has, however, coded such information simply by indicating that the test compound is altered (using 

 Symbol FE in Field T-2, with no coding in Column 60 or 61) to the product coded in Field D. 



In Column 61, letters A through I have not been used in making symbols for the FE-- series 

 because, with this series, the IBM 12 zone punch (Symbol *) has been assigned to the purpose 

 explained above. 



27. Symbols of the series FF--; excretion, secretion, etc. (elimination) of the test compound ; 

 elimination of materials foreign to the test organism or foreign to a specific path of 

 elimination which can be affected by the test compound 



When Field T-2 is coded to describe the process of excretion, secretion, or vomiting of the 

 test compound (Symbol FF-B), only Symbol 7 of Field T-l can be used. When Field T-2 is coded to 

 describe excretion, secretion, or vomiting of any foreign material other than the test compound, Field 

 T-l can be coded to indicate the test compound's increasing, decreasing, or preventing (Symbol 1, 2, 

 or 3), being essential for (Symbol 7), antagonizing, synergizing, simulating, or being additive with a 

 secondary compound's effect on (Symbol 8, 9, A, or C) the secretion, excretion, or vomiting of the 

 foreign material. 



When using Symbol 8, 9, A, or C in Field T-l, Field D must be coded with the compound 

 antagonized, synergized, simulated, or whose action is additive with the test compound; under these 



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