Ngomphumo wonyaka ongaphezulu kweetoni ezingama-700,000, i-glyphosate yeyona herbicide isetyenziswa kakhulu kwaye inkulu ehlabathini. Ukumelana nokhula kunye neengozi ezinokubakho kwindalo esingqongileyo kunye nempilo yabantu ezibangelwa kukusetyenziswa gwenxa kwe-glyphosate kuye kwatsala ingqalelo enkulu.
Ngomhla wama-29 kuCanzibe, iqela likaNjingalwazi uGuo Ruiting elivela kwi-State Key Laboratory of Biocatalysis and Enzyme Engineering, esekwe ngokudibeneyo yiSikolo seSayensi yoBomi kwiYunivesithi yaseHubei kunye namasebe ephondo nawobuphathiswa, lipapashe iphepha lophando lwamva nje kwiJournal of Hazardous Materials, lihlalutya uhlalutyo lokuqala lwengca ye-barnyard. I-aldo-keto reductase evela kwi-(A malignant paddy weed) kunye ne-AKR4C17 zikhuthaza indlela yokusabela kokubola kwe-glyphosate, kwaye ziphucula kakhulu ukusebenza kakuhle kokubola kwe-glyphosate yi-AKR4C17 ngokuguqulwa kwemolekyuli.
Ukwanda kokumelana ne-glyphosate.
Ukususela oko yaqala ukusetyenziswa ngeminyaka yoo-1970, i-glyphosate ibisoloko ithandwa kwihlabathi liphela, kwaye kancinci kancinci iye yaba yi-herbicide ebiza kancinci, esetyenziswa kakhulu kwaye ivelisa kakhulu. Ibangela ukuphazamiseka kwe-metabolic kwizityalo, kuquka ukhula, ngokuthintela ngokukodwa i-5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), i-enzyme ephambili ebandakanyeka ekukhuleni kwezityalo kunye ne-metabolism.
Ngoko ke, ukuzala izityalo eziguqulweyo ezimelana ne-glyphosate kunye nokusebenzisa i-glyphosate endle yindlela ebalulekileyo yokulawula ukhula kwezolimo zanamhlanje.
Nangona kunjalo, ngenxa yokusetyenziswa kakhulu nokusetyenziswa gwenxa kwe-glyphosate, ukhula oluninzi luye lwakhula kancinci kancinci lwaza lwaphuhlisa ukunyamezelana okuphezulu kwe-glyphosate.
Ukongeza, izityalo eziguqulwe ngokwemfuza ezimelana ne-glyphosate azinakubola i-glyphosate, nto leyo ebangela ukuqokelelwa nokudluliselwa kwe-glyphosate kwizityalo, nto leyo enokusasaza ngokulula kwikhonkco lokutya ize ibeke impilo yabantu esichengeni.
Ngoko ke, kungxamisekile ukufumanisa ii-genes ezinokonakalisa i-glyphosate, ukuze kukhuliswe izityalo eziguqulweyo ezimelana ne-glyphosate ezineentsalela ze-glyphosate ezisezantsi.
Ukusombulula isakhiwo sekristale kunye nendlela yokusabela kwe-catalytic yee-enzymes ezitshabalalisa i-glyphosate ezivela kwizityalo
Ngowama-2019, amaqela ophando aseTshayina nase-Australia achonge ii-aldo-keto reductases ezimbini ezitshabalalisa i-glyphosate, i-AKR4C16 kunye ne-AKR4C17, okokuqala ngqa kwingca ye-barnyard enganyangekiyo yi-glyphosate. Bangasebenzisa i-NADP+ njenge-cofactor yokunciphisa i-glyphosate ibe yi-aminomethylphosphonic acid engeyiyo ityhefu kunye ne-glyoxylic acid.
I-AKR4C16 kunye ne-AKR4C17 zezona enzymes zokuqala ezixeliweyo ezitshabalalisa i-glyphosate eziveliswa kukuguquka kwendalo kwezityalo. Ukuze kuhlolwe ngakumbi indlela ye-molecular yokubola kwe-glyphosate, iqela likaGuo Ruiting lisebenzise i-X-ray crystallography ukuhlalutya ubudlelwane phakathi kwezi enzymes zimbini kunye ne-cofactor high. Ulwakhiwo oluntsonkothileyo lwesisombululo lutyhile indlela yokubopha ye-ternary complex ye-glyphosate, i-NADP+ kunye ne-AKR4C17, kwaye lucebise indlela yokusabela kwe-catalytic ye-AKR4C16 kunye ne-AKR4C17-mediated glyphosate degradation.
Ulwakhiwo lwe-AKR4C17/NADP+/glyphosate complex kunye nendlela yokusabela kokuwohloka kwe-glyphosate.
Ukuguqulwa kweemolekyuli kuphucula ukusebenza kakuhle kokuwohloka kwe-glyphosate.
Emva kokufumana imodeli yesakhiwo esihle esinemilinganiselo emithathu ye-AKR4C17/NADP+/glyphosate, iqela likaNjingalwazi uGuo Ruiting liphinde lafumana iproteni eguqulweyo i-AKR4C17F291D enokwanda kwe-70% ekusebenzeni kakuhle kokonakala kwe-glyphosate ngohlalutyo lwesakhiwo se-enzyme kunye noyilo oluqiqileyo.
Uhlalutyo lomsebenzi wokonakalisa i-glyphosate we-AKR4C17 mutants.
“Umsebenzi wethu utyhila indlela esebenza ngayo i-AKR4C16 kunye ne-AKR4C17 ekukhuthazeni ukubola kwe-glyphosate, nto leyo ebeka isiseko esibalulekileyo sokuguqulwa ngakumbi kwe-AKR4C16 kunye ne-AKR4C17 ukuphucula ukusebenza kakuhle kokubola kwe-glyphosate.” Umbhali ohambelanayo wephepha, uNjingalwazi oNcedisayo uDai Longhai weYunivesithi yaseHubei uthe bakhe iproteni eguqulweyo i-AKR4C17F291D enokuphucula ukusebenza kakuhle kokubola kwe-glyphosate, ebonelela ngesixhobo esibalulekileyo sokulima izityalo eziguquguqukayo ze-glyphosate ezine-residues ephantsi ye-glyphosate kunye nokusebenzisa iibhaktheriya zobunjineli be-microbial ukonakalisa i-glyphosate kwindalo esingqongileyo.
Kubikwa ukuba iqela likaGuo Ruiting kudala libandakanyeka kuphando malunga nohlalutyo lwesakhiwo kunye nengxoxo yendlela yokusebenza kwee-enzymes ze-biodegradation, ii-synthases ze-terpenoid, kunye neeproteni ezijoliswe kwiziyobisi zezinto ezinobuthi neziyingozi kwindalo esingqongileyo. ULi Hao, umphandi oncedisayo uYang Yu kunye nomfundisi uHu Yumei kwiqela ngababhali bokuqala beli phepha, kwaye uGuo Ruiting kunye noDai Longhai ngababhali abahambelanayo.
Ixesha lokuthumela: Juni-02-2022