Specific interaction of jacalin with phycocyanin, a fluorescent phycobiliprotein.
Recent research has shown that, like porphyrins, phycocyanin (PC) too can produce singlet oxygen upon excitation with the appropriate radiation and hence could be useful in photodynamic therapy (PDT) for cancer. Unlike porphyrins, PC has the advantage of being a non-toxic, non-carcinogenic, soluble protein. However, the challenge would be to target the fluorescent phycobiliprotein to malignant cells. We report here that the tumor-specific lectin, jacalin, binds PC specifically in a carbohydrate-independent manner and with affinities better than that for porphyrins. Hence the lectin could prove to be a useful carrier for targeted delivery of PC. The interaction involves both ionic and hydrophobic interactions and more than one contact site.
Pandey
Gunjan
G
Department of Bio-Sciences, Jamia Millia Islamia, New Delhi 110 025, India.
Fatma
Tasneem
T
Cowsik
Sudha M
SM
Komath
Sneha Sudha
SS
D005453:Fluorescence; D057927:Hydrophobic and Hydrophilic Interactions; D010778:Photochemotherapy; D052979:Phycobiliproteins / Q000737:chemistry*; D010798:Phycocyanin / Q000737:chemistry*; D037121:Plant Lectins / Q000737:chemistry*; D026082:Singlet Oxygen / Q000737:chemistry; D013050:Spectrometry, Fluorescence
D052979:Phycobiliproteins; D037121:Plant Lectins; C043696:jacalin; D010798:Phycocyanin; D026082:Singlet Oxygen