AMINO ACIDS SEQUENCE ANALYSIS ON COLLAGEN

1988), p1 (Black et al., 1991) - p20 (Cowan and Whittaker, 1990); and p17 (Rosema, 1988)
- p20 (Cowan and Whittaker, 1990).

÷ Two variables (hydrophobic or hydrophilic character scales) followed a normal
distribution: p3 (Wimley and White, 1996), and p18 (Welling et al., 1985).

÷ A total number of nineteen factors have been identified. The amino acids contribution on
factors based on correlation matrix, expressed as extreme values (maximum and
minimum) was: p9 (Rose et al., 1985) with two maximum and one minimum, p13
(Abraham and Leo, 1987) with three minimum, p18 (Welling et al., 1985) with one
maximum and three minimum.

Amino Acids on Collagen Type I

The frequency of apparition of amino acids in the alpha 1 and 2 chains according with
investigated specie is presented in Table 2.

Table 2

Amino acids distribution in collagen chains

Amino acid (aa)		Homo sapiens		Bos taurus		Canis lupus		Rattus norvegicus		Danio rerio
Name___________	Abb	HS_a1	HS_a2	BT_a1	BT_a2	CL_a1	CL_a2	TN_a1	RN_a2	DR_a1	DR_a2
Alanine_____________	A	115	130	143	126	138	123	125	108	162	137
Cysteine_____________	C	____10	______9	____18	______9	____18	______9	0	0	_____18	______8
Aspartate____________	D	____41	____43	____64	____43	____64	____43	_____34	____23	____62	____46
Glutamate___________	E	____57	____66	____76	____64	____74	____65	_____54	_____48	____82	____56
Phenylalanine________	F__	____14	____22	____24	____23	____25	____21	______13	_____14	____28	____21
Glycine______________	G	329	381	389	380	390	381	344	345	382	382
Histidine_____________	H	_______3	_____15	______9	____12	_____8	____12	________3	______7	_____10	_____11
Isoleucine____________	J__	____10	____32	____25	_____35	____26	____34	______8	_____19	____36	____30
Lysine______________	K	____38	____50	____57	____50	____56	____50	_____35	_____21	____58	____50
Leucine_____________	L__	____29	____61	____50	____60	____47	____59	_____21	_____34	____37	____57
Methionine__________	M	______8	____10	_____13	______9	_____15	_____11	______8	_______5	____25	____17
Asparagine__________	N	____14	____41	____29	____43	____31	____42	_____12	_____21	____35	____44
Proline_______________	P__	230	231	279	236	278	235	126	113	235	223
Glutamine___________	Q	____30	____33	____51	____36	____50	____35	____25	____23	____40	____37
Arginine_____________	R	____51	____72	____70	____73	____71	____73	_____52	_____55	____68	____72
Serine________________	_S___	____35	____52	____58	____54	____58	____52	_____39	____27	____62	____67
Threonine___________	T	____23	____42	____44	____43	____47	____51	_____16	_____21	____53	____40
Valine_______________	V	____28	____55	____42	____50	____42	____50	18	39	____39	____35
Tryptophan_________	W	_________1	______5	_____6	______5	_____6	______5	0	0	______6	______5
Tyrosine_____________	Y	_______3	____16	____16	_____13	____16	_____15	5	1	______9	_____14
Unspecified or unknown	X	_____о	_____0	_____0	_____0	_____0	_____0	116	102	______0	______0
_______________________Total		1069	1366	1463	1364	1460	1366	1054	1026	1447	1352

Looking at the data from Table 2 it can be observed that without any exceptions the
glycine is the amino acid most abundant in both chains and to all investigated species.
Analyzing the amino acids distribution on α1 comparing with α2 within group, statistical
significant differences was been identified in two species: Homo sapiens (Proline, p =
0.0019), and Danie rerio (Glutamate, p = 0.0157). Note that the Rattus norvegicus specie is
the one with unspecified or unknown amino acids (11% for α1 chain and almost 10% form α2
chains) and without any identified Cysteine or Tryptophan amino acids in sequences of α1 or
α2 chain. The strings similarity matrix on collagen chains, expressed as percent of similarity
in amino acids within and between species, was calculated (see Table 3). Following are true
regarding the string similarities between species: ■ a good similarity on α1 chain exists

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AMINO ACIDS SEQUENCE ANALYSIS ON COLLAGEN

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