Isolation of Jatropha Curcas Seeds Isolectins with Variable Affinity for Human and Animal Blood Types

Background: Lectins are carbohydrate-binding protein which agglutinate glycoconjugates in a reversible way, they are with wide applications in biological and medical sciences. Jatropha curcas belongs to the family euphorbiaceae and is distributed in many tropical and subtropical countries. The toxicity of this plant is known for long ago and has been attributed to several components among which is a protein called curcin. Methods: Jatropha curcas seeds were pulverized and protein was extracted with suitable buffer. Protein extract thus obtained had undergone successive protein precipitations by salting-out using (NH4)2SO4 (AS) at 40, 60, and 80% saturations. Lectin activity was detected by hemagglutination method using human- and animal blood types. AS-precipitated protein fractions that possess lectin activity were tested for their antimicrobial activity against the pathogenic Staphylococcus aureus, Escherichia coli, Bacillus aueras, and Candida albicans. Results: At least three isolectins (Lec40, Lec60, and Lec80) were detected by hemagglutination (HA) and isolated by AS fractionation from the crude Jatropha curcas seed extract (CExt). The isolectins exhibited different tendency toward human and animal blood types. None of the isolectins could inhibit any of the used bacterial strains and Candida albicans. Conclusions: In this study, though the detected lectins resemble their counterpart legume lectins, they, however, showed apparently unique and variable behavior toward human and animal blood types. Which might emphasize on the need for further structural analysis on the affinity sites of these proteins. Keywords: Jatropha curcas; euphorbiaceae; lectin; hemagglutination; antimicrobial activit

Phoenix dactylifera (date palm; Arecaceae) putative lectin homologs: Genome-wide search, architecture analysis, and evolutionary relationship

The date palm, Phoenix dactylifera, is a vital crop in nations in the Middle East and North Africa. The date palm was thought to have outstanding traditional medicinal value because it was abundant in phytochemicals with diverse chemical structures. The date palm's ability to withstand harsh environments could be partly attributed to a class of proteins known as lectins, which are carbohydrate-binding proteins that can bind sugar moieties reversibly and without changing their chemical structures. After scanning the genome of P. dactylifera (GCF 009389715.1), this in silico study discovered 196 possible lectin homologs from 11 different families, some specific to plants. At the same time, others could also be found in other kingdoms of life. Their domain architectures and functional amino acid residues were investigated, and they yielded a 40% true-lectin with known conserved carbohydrate-binding residues. Further, their probable subcellular localization, physiochemical and phylogenetic analyses were also performed. Scanning all putative lectin homologs against the anticancer peptide (ACP) dataset found in the AntiCP2.0 webpage identified 26 genes with protein kinase receptors (Lec-KRs) belonging to 5 lectin families, which are reported to have at least one ACP motif. Our study offers the first account of Phoenix-lectins and their organization that can be used for further structural and functional analysis and investigating their potential as anticancer proteins