The amino acid sequences of the α 1 and α 2 subunits of the isoelectins from seeds of Lathyrus ochrus (L) DC

Abstract

The complete amino acid sequences of the al and a2 subunits of the isolectins (LoL I and LoL II) from seeds of Lathyrus ochrus were determined by analysis of peptides derived from the proteins by digestion with trypsin, chymotrypsin and the S. aureus V8 protease. Both subunits consisted of single polypeptide chains of 53 amino acids, which differed from one another in only 4 positions near their C-termini, and exhibited high homology to the light (a) chains of the lectins from Lathyrus sativus, L. odoratus and a number of other legume seeds.Lathyrus ochrus isoelectin a Subunit Amino acid sequence Homology Legume lectin

The fourth immunoglobulin-like domain of NCAM contains a carbohydrate recognition domain for oligomannosidic glycans implicated in association with L1 and neurite outgrowth.

“…A few amino acids of the consensus sequence for carbohydrate recognition domains of C-type lectins (Weis et al, 1991) could also be aligned at corresponding positions within this peptide. Most surprisingly, the carboxy-terminal half of the fourth and the beginning of the fifth immunoglobulin-like domains of NCAM showed a similarity of 43 % to the alpha chains of a group of mannose/glucose specific plant lectins from leguminoses (Richardson et al, 1984). Thus, as to our knowledge, we describe here for the first time a sequence homology between animal and plant lectins.…”

“…We further compared the amino acid sequence of the fourth immunoglobulin-like domain of NCAM without the alternatively spliced 7r exon (Santoni et al,, 1989) with the sequence of the carbohydrate recognition domain four of the human mannose receptor, shown to be functionally most active in carbohydrate binding (Taylor et al, 1992), with the consensus sequence for C-type lectins according to Weis et al (1991), and to the alpha chain of the mannose/glucose specific lectin from Lathyrus ochrus (Richardson et al, 1984). We found a similarity of 37% at the protein level between the fourth and the beginning of the fifth immunoglobulin-like domain of mouse NCAM (from amino acid 323 to 439) and the carbohydrate recognition domain four of the human mannose receptor (from amino acid 673 to 781).…”

“…Lathyrus ochrus; Richardson et al, 1984) with the fourth immunoglobulin-like domain of NCAM was performed using the following pa- and Vicia cracca (Bauman et al, 1982), was used for this comparison. The fourth immunoglobulin-like domain showed a similarity of 43 % at the protein level to the alpha chain of Lathyrus ochrus lectin (total length 53 amino acids) (Fig.…”

The Biochemistry and Cell Biology of Embryo Storage Proteins

“…The subunits from G. max are referred to as glycinins, and the two subfamilies of subunits belong to either Group-lor Group-2 (Nielsen, 1984). The gene s that encode each subunit (Fischer and Goldberg, 1982;Marco et al, 1984;Scallon et al, 1987;Nielsen et al, 1989), as well as the proteins produced from them (Moreira et al, 1981;Staswick et al, 1981;1984 a,b), have been purified and characterized. Subunits that belong to the same subfamily share greater than 90% homology, but there is only about 50% homology among members from different subfamilies.…”

Post-translational peptide bond formation during concanavalin A processing in vitro

“…Seed proteins found in this compartment might be used as a store of amino acids for the developing seedling or might have a role in defence. In dicotyledons, endoproteolytic cleavage at the peptide bond immediately C-terminal to an asparagine residue has been implicated in the biosyntheses of vacuolar and protein storage vesicle components such as storage proteins [1][2][3][4][5][6][7][8], defence-related proteins [9,10], ricin [11] and lectins [12][13][14][15][16][17][18][19][20][21][22].…”