Chemoattractants and chemorepellents Chemoattractants and chemorepellents are inorganic or organic substances possessing chemotaxis-inducer effect in motile cells. These chemotactic ligands create chemical concentration gradients that organisms, prokaryotic and eukaryotic, move toward or away from, respectively. right|250x250px|float Effects of chemoattractants are elicited via chemoreceptors such as methyl-accepting chemotaxis proteins (MCP). MCPs in E.coli include Tar, Tsr, Trg and Tap. Chemoattracttants to Trg include ribose and galactose with phenol as a chemorepellent. Tap and Tsr recognize dipeptides and serine as chemoattractants, respectively.
ChEmoaTtractaNts ANd chemOREpeLLentS chEmoAttRaCTanTs aNd CHemorepellents ARe InorganIc or orGAniC substaNcEs possessinG ChemOtAXIs-iNDuCeR efFect in mOTIle cells THese chemotactic LigAndS crEate CHemicaL ConcEnTration graDIents thAt orgANismS prokaRyoTic AnD eUkAryotIc MoVe toward Or awaY fRom REspectiveLY rIghT|250X250px|fLoAt efFects of ChemoattractaNTs ArE eLiciteD vIa cheMorecepTORs sUCH as mEthYl-aCcEpting ChemotAxis proteiNS (mcp) mcps In eCOLi iNclude tar TSr trG AnD tAp cHemoaTtRacttaNTS tO tRg incLude riBose and GaLaCtoSe wiTH pHeNoL as A chEMorepeLLent tap ANd TSr reCoGNize dIpeptIDes and sErinE aS cHemOAttRActaNTs resPectIVely