Four Stereochemical Types of Protein Amino Acids: Synchronic Determination with Chemical Characteristics, Atom and Nucleon Number

On Rakočević’s Amino Acid Biosynthetic Precursors Relations

“…In his seminal work on the classification of the twenty amino acids, the building-blocks of the proteins and also of many other functional tools, with his collaborator (Rakočević and Jokić, 1996), Rakočević, in particular, reduced the list of the twenty canonical amino acids to a "compressed" list of only 6 (or 7) of their biosynthetic precursors, according to well established and known facts in biochemistry (Berg et al, 2003, p.670). The order and hierarchy of the six (source) bio-precursors, and also the corresponding amino acids are as follows:…”

“…Let us note, importantly and for later use that the first three precursors are less complex and the last three are more complex. At the same time the first and the two last are phosphoprecursors (i.e., phosphate atom containing) and the other three are non-phospho precursors (Rakočević and Jokić, 1996). These two chemical categorization-partitions together with two other categorizationpartitions linked to the mathematical nature of their order n, odd/even and prime/nonprime, will play a central role in Sections 2-5.…”

Genetic Code as a Coherent System

“…Regarding to the second alphabet of GC, the amino acid alphabet, it was shown that 20 AAs are classified into four stereochemical types (Popov, 1989;Rakočević and Jokić, 1996), as it is here presented in Figure 1 and Tables 2.1, 2.2 and Table 3. Table 2.1.…”

“…six and six, and then, three and three doublets) and three possible distinctions for triplets (i.e. four and four, then two and two, and, finally, one and one triplet)" (Rakočević & Jokić, 1996). corresponding to the symmetry in the simplest case (Marcus, 1989) and to the zeroth case of generalized golden mean (Stakhov, 1989;Rakočević, 2004b). On the other hand, the ratio of the differences of the number of atoms in the integrated system is 8:12 = 2:3.…”

“…By this, the order of doublets and triplets is established with a strict atom number increasing from one to another next amino acid in correspondence with the involvement of the biosynthetic precursors one after another: first, the less complex and then the more complex precursors (cf. Table 1 in Rakočević & Jokić, 1996).…”