Domain construction of cherry-tomato lectin: relation to newly found 42-kDa protein.
In the early stage of ripening of cherry-tomato fruits (Lycopersicon esculentum var. cherry), the lectin activity increased logarithmically and reached a plateau at day 10 after flowering. During purification of lectin from ripe and unripe fruits, a 42-kDa protein was found abundantly in unripe fruits. The protein cross-reacted with anti-cherry-tomato-lectin serum, retained chitin-binding ability, but showed no lectin activity. Comparative studies between the structure of the lectin and the 42-kDa protein were done. N-Terminal amino acid sequences of the lectin, peptides derived from the S-pyridylethylated lectin, and fragments generated by limited proteolysis of the native lectin showed that the lectin was comprised of three domains, Hyp-rich, Cys-rich, and Gln-rich, and the alignment of them was as this order from the N-terminus. Studies on the 42-kDa protein showed that it contained two of the three domains, Cys-rich and Gln-rich, but the amino acid sequence analysis showed that the protein should be a product of another gene.
Department of Bioresources Chemistry, Faculty of Horticulture, Chiba University, Matsudo, Japan.
Y
Y
Naito
T
T
Minamihara
A
A
Ando
T
T
Marutani
S
S
Oguri
Y
Y
Nagata
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D002686:Chitin / Q000378:metabolism; D005638:Fruit / Q000737:chemistry; D015151:Immunoblotting; D037102:Lectins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D018551:Solanum lycopersicum / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D008969:Molecular Sequence Data; D037121:Plant Lectins; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary
D000596:Amino Acids; D037102:Lectins; D037121:Plant Lectins; D010940:Plant Proteins; C034981:tomato lectin; D002686:Chitin