Bioremediation of organophosphorus pesticides in contaminated foodstuffs using probiotics has been increasingly under the spotlight in recent years,though the biodegradation mechanism and derived intermediate products...Bioremediation of organophosphorus pesticides in contaminated foodstuffs using probiotics has been increasingly under the spotlight in recent years,though the biodegradation mechanism and derived intermediate products remain unclear.This study aimed to help fill this knowledge gap and examined the degradation mechanism of organophosphorus pesticide,chlorpyrifos,in milk by Lactobacillus delbrueckii ssp.bulgaricus using gas chromatography-tandem mass spectrometry(GC-MS/MS)combined with transcriptome analysis.After the strain was cultured for 20 h in the presence of chlorpyrifos,differential expressions of 383 genes were detected,including genes probably implicated during chlorpyrifos degradation such as those related to hydrolase,phosphoesterase,diphosphatase,oxidoreductase,dehydratase,as well as membrane transporters.GC-MS/MS analysis revealed the changes of secondary metabolites in L.bulgaricus during milk fermentation due to chlorpyrifos stress.6-Methylhexahydro-2H-azepin-2-one,2,6-dihydroxypyridine and methyl 2-aminooxy-4-methylpentanoate as intermediates,along with the proposed pathways,might be involved in chlorpyrifos biodegradation by L.bulgaricus.展开更多
Oryza sativa L. ssp. japonica and indica exhibit different sensitivity to photoinhibition and they show different stability of their core proteins D1 in the chloroplast photosystem Ⅱ. Using in situ hybridization, psb...Oryza sativa L. ssp. japonica and indica exhibit different sensitivity to photoinhibition and they show different stability of their core proteins D1 in the chloroplast photosystem Ⅱ. Using in situ hybridization, psbA, the gene encoding D1 protein of O. sativa ssp. japonica cv. 9516, and that of O. sativa ssp. indica cv. Shanyou 63 was cloned. As revealed by homology comparison of their sequences, the sequences are identical in the regions of promoter and 5′-UTR; differences are found in individual bases in the coding region all of which, being in the third position of respective codons, however, do not affect the amino acids coded finally; a difference is noted in the length of the oligo-U sequence in the region of 3′-UTR. It is thus apparent that, rather than a result of any difference in the amino acid sequences, the differences in the sensitivity to photoinhibition of D1 proteins between japonica and indica rice may be related to the upstream factors that regulate expression of psbA or to differences of photoprotective mechanisms.展开更多
基金supported by Natural Science Foundation of China(41907357)Natural Science Foundation of Shandong(ZR2019PC048)the Key R&D project of Shandong Province(2021TZXD007).
文摘Bioremediation of organophosphorus pesticides in contaminated foodstuffs using probiotics has been increasingly under the spotlight in recent years,though the biodegradation mechanism and derived intermediate products remain unclear.This study aimed to help fill this knowledge gap and examined the degradation mechanism of organophosphorus pesticide,chlorpyrifos,in milk by Lactobacillus delbrueckii ssp.bulgaricus using gas chromatography-tandem mass spectrometry(GC-MS/MS)combined with transcriptome analysis.After the strain was cultured for 20 h in the presence of chlorpyrifos,differential expressions of 383 genes were detected,including genes probably implicated during chlorpyrifos degradation such as those related to hydrolase,phosphoesterase,diphosphatase,oxidoreductase,dehydratase,as well as membrane transporters.GC-MS/MS analysis revealed the changes of secondary metabolites in L.bulgaricus during milk fermentation due to chlorpyrifos stress.6-Methylhexahydro-2H-azepin-2-one,2,6-dihydroxypyridine and methyl 2-aminooxy-4-methylpentanoate as intermediates,along with the proposed pathways,might be involved in chlorpyrifos biodegradation by L.bulgaricus.
文摘Oryza sativa L. ssp. japonica and indica exhibit different sensitivity to photoinhibition and they show different stability of their core proteins D1 in the chloroplast photosystem Ⅱ. Using in situ hybridization, psbA, the gene encoding D1 protein of O. sativa ssp. japonica cv. 9516, and that of O. sativa ssp. indica cv. Shanyou 63 was cloned. As revealed by homology comparison of their sequences, the sequences are identical in the regions of promoter and 5′-UTR; differences are found in individual bases in the coding region all of which, being in the third position of respective codons, however, do not affect the amino acids coded finally; a difference is noted in the length of the oligo-U sequence in the region of 3′-UTR. It is thus apparent that, rather than a result of any difference in the amino acid sequences, the differences in the sensitivity to photoinhibition of D1 proteins between japonica and indica rice may be related to the upstream factors that regulate expression of psbA or to differences of photoprotective mechanisms.
