BanLec
BanLec(alsoBanLec-IorBanana lectin) is alectinfrom thejacalin-related lectin family isolated from the fruit of thebananasMusa acuminata[1]andMusa balbisiana.[2]BanLec is one of the predominantproteinsin the pulp of ripe bananas[3]and has binding specificity formannoseand mannose-containingoligosaccharides.[2]A 2010 study reported that BanLec was a potent inhibitor ofHIVreplication.[1]
Activity[edit]
BanLec has a number of similarities toConcanavalin Aand binds tomannose-relatedcarbohydratestructures.[2]It was discovered due to its highlyimmunogenicproperties—BanLec induces a strongIgG4antibodyresponse[2]—and appears to be an importantantigeninvolved inbanana allergies.[4]
BanLecexpressioncan be induced by theplant hormonemethyl jasmonate.[3]
Structure and stability[edit]
BanLec exists as ahomodimerof two identical 15kDasubunits[3]and has also been reported as a tetramer complex.[5]The protein is highly stable,unfoldingonly at high temperatures[6][7]
All jacalin-related lectins feature type Ibeta-prismfolding motifs (the beta-prism I fold is like a perfect beta-prism with each side made up of a four-strandedgreek key motif), but BanLec is the first jacalin-related lectin from themonocotfamily of plants, while all other members aredicots;other monocot mannose-binding lectins exhibit beta-prism II folding instead.[7]
BanLec features strong intersubunit interactions with high levels ofhydrogen bondingandwater bridgesallowing resistance todenaturingwhen exposed to high temperatures or high concentrations ofchaotropessuch asguanidium hydrochloride.[7]Crystal structuresof BanLec suggest that the lectin has twosaccharidebinding sites.[8]
HIV inhibition[edit]
In 2010, BanLec was reported to be apotentinhibitor ofHIVreplication.[1][9]Researchers at theUniversity of Michigandetermined that BanLec bound to theHIV-1envelope proteingp120,which is high in sugar content, inhibiting viral entry into human cells.[1][9]The researchers suggest that such an inhibitor of HIV infection may find use as atopicaltreatment, such as avaginalmicrobicide,and may be cheaper to produce than current antiviral topical treatments.[10]
References[edit]
- ^abcdSwanson MD, Winter HC, Goldstein IJ, Markovitz DM (March 2010)."A Lectin Isolated from Bananas Is a Potent Inhibitor of HIV Replication".J. Biol. Chem.285(12): 8646–55.doi:10.1074/jbc.M109.034926.PMC2838287.PMID20080975.
- ^abcdKoshte VL, van Dijk W, van der Stelt ME, Aalberse RC (December 1990)."Isolation and characterization of BanLec-I, a mannoside-binding lectin from Musa paradisiac (banana)".Biochem. J.272(3): 721–6.doi:10.1042/bj2720721.PMC1149768.PMID2268297.
- ^abcPeumans WJ, Zhang W, Barre A, et al. (September 2000)."Fruit-specific lectins from banana and plantain".Planta.211(4): 546–54.Bibcode:2000Plant.211..546P.doi:10.1007/s004250000307.PMID11030554.
- ^Koshte VL, Aalbers M, Calkhoven PG, Aalberse RC (1992). "The potent IgG4-inducing antigen in banana is a mannose-binding lectin, BanLec-I".Int. Arch. Allergy Immunol.97(1): 17–24.doi:10.1159/000236090.PMID1582693.
- ^Hopper, Jonathan T.S.; Ambrose, Stephen; Grant, Oliver C.; Krumm, Stefanie A.; Allison, Timothy M.; Degiacomi, Matteo T.; Tully, Mark D.; Pritchard, Laura K.; Ozorowski, Gabriel; Ward, Andrew B.; Crispin, Max;Doores, Katie J.;Woods, Robert J.; Benesch, Justin L.P.; Robinson, Carol V.; Struwe, Weston B. (May 2017)."The Tetrameric Plant Lectin BanLec Neutralizes HIV through Bidentate Binding to Specific Viral Glycans".Structure.25(5): 773–782.e5.doi:10.1016/j.str.2017.03.015.PMC5556678.PMID28434916.
- ^Gupta G, Vishveshwara S, Surolia A (March 2009)."Stability of dimeric interface in banana lectin: Insight from molecular dynamics simulations".IUBMB Life.61(3): 252–60.doi:10.1002/iub.162.PMID19189367.
- ^abcGupta G, Sinha S, Surolia A (August 2008). "Unfolding energetics and stability of banana lectin".Proteins.72(2): 754–60.doi:10.1002/prot.21961.PMID18260105.
- ^Meagher JL, Winter HC, Ezell P, Goldstein IJ, Stuckey JA (October 2005)."Crystal structure of banana lectin reveals a novel second sugar binding site".Glycobiology.15(10): 1033–42.doi:10.1093/glycob/cwi088.PMID15944373.
- ^ab"Study: Chemical in Bananas Could Help Fight HIV",Fox News Channel,March 16, 2010
- ^"Protein in bananas could help block spread of HIV, University of Michigan researchers say",AnnArbor.com, March 15, 2010