TABLE 1.

Assignment of the reverse-phase fractions from the venoms of Crotalus tigris, isolated as in Fig. 1, to protein families by N-terminal Edman sequencing, mass spectrometry, and collision-induced fragmentation by nESI-MS/MS of selected peptide ions from in-gel digested protein bands separated by SDS-PAGE (insert in Fig. 1). In MS/MS-derived sequences, X = Ile or Leu; Z, pyrrolidone carboxylic acid; B, Lys or Gln. Unless other stated, for MS/MS analyses, cysteine residues were carbamidomethylated; Molecular masses of native proteins were determined by electrospray-ionization (± 0.02%) or MALDI-TOF (± 0.2%) mass spectrometry. Apparent molecular masses were determined by SDS-PAGE of reduced samples. “de novo”, peptide sequence determined by manual interpretation of MS/MS spectra that did not produce any hit by MASCOT search. Peptide sequences from the MS/MS-based assigned proteins matching ions present in the tryptic peptide mass fingerprint spectra are labeled with asterisks.

HPLC Fraction	N-terminal sequence	Molecular mass	Peptide ion		MS/MS-derived sequence	Mowse score	Protein family
			m/z	z
1	AGEECDCGSPANP	7320 Da					Disintegrin
2	SPEXCQG SYGCYCG	9 kDa					Mojave toxin acid chain [P18998]
3	HLLQFNKMIKFETRK	14187 Da	649.8	2	YGYMFYPDSR	75	Mojave toxin basic chain [P62023]
			871.8	2	GTWCEEQICECDR	75
			2158.9	1	NAIPFYAFYGCYCGWGGR*
			1978.0	1	SLSTYKYGYMFYPDSR*
4	ND	36 kDa	692.3	2	ZAMPFMEVYER	de novo	svVEGF
5	SVDFDSESPRKPEIQ	24 kDa	569.6	2	SVDFDSESPR	36	CRISP
			769.3	2	MEWYPEAAANAER	68
6	VVGGDECNINEHR	31 kDa	749.8	2	VVGGDECDINEHR	60	Serine proteinase
			657.4	2	XGNWGSXTPXTR	de novo
			552.6	2	TXCAGXVQGGK	88
7,10	VIGGDECNINEHRFL	31 kDa	756.8	2	VIGGDECNINEHR	42	Serine proteinase [~ ABY65929]
			1321.8	1	HILIYVGVHDR *
			1770.9	1	ILCAGVLEGGIDTCHR*
8,9	ND	46 kDa	578.3	3	MYDXVNVXTPXYHR	42	PIII-SVMP (~ Q9DGB9)
			1155.6	1	EGNHYGYCR*
			1283.8	1	EGNHYGYCRK*
			604.6	3	QGAQCAEGLCCDQCR	35