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Antonio Jimenez - One of the best experts on this subject based on the ideXlab platform.

  • the Biosynthetic Pathway of the aminonucleoside antibiotic puromycin as deduced from the molecular analysis of the pur cluster of streptomyces alboniger
    Journal of Biological Chemistry, 1996
    Co-Authors: Jose Antonio Tercero, Juan Carlos Espinosa, Rosa Ana Lacalle, Antonio Jimenez
    Abstract:

    Abstract The pur cluster which encodes the puromycin Biosynthetic Pathway from Streptomyces alboniger was subcloned as a 13-kilobase fragment in plasmid pIJ702 and expressed in an apparently regulated manner in the heterologous host Streptomyces lividans. The sequencing of a 9.1-kilobase DNA fragment completed the sequence of pur. This permitted identification of seven new open reading frames in the order: napH, pur7, pur10, pur6, pur4, pur5, and pur3. The latter is followed by the known pac, dmpM, and pur8 genes. Nine open reading frames are transcribed rightward as a unit in opposite direction to that of the pur8 gene which is expressed as a monocistronic transcript from the rightmost end. napH encodes the known N-acetylpuromycin N-acetylhydrolase. The deduced products from other open reading frames present similarities to: NTP pyrophosphohydrolases (pur7), several oxidoreductases (pur10), the putative LmbC protein of the lincomycin Biosynthetic Pathway from Streptomyces lincolnensis (pur6), S-adenosylmethionine-dependent methyltransferases (pur5), a variety of presumed aminotransferases (pur4), and several monophosphatases (pur3). According to these similarities and to previous biochemical work, a puromycin Biosynthetic Pathway has been deduced. No cluster-associated regulatory gene was found. However, both pur10 and pur6 genes contain a TTA codon, which suggests that they are translationally controlled by the bldA gene product, a specific tRNA.

  • the Biosynthetic Pathway of the aminonucleoside antibiotic puromycin as deduced from the molecular analysis of the pur cluster of streptomyces alboniger
    Journal of Biological Chemistry, 1996
    Co-Authors: Jose Antonio Tercero, Rosa Ana Lacalle, Carlos J Espinosa, Antonio Jimenez
    Abstract:

    The pur cluster which encodes the puromycin Biosynthetic Pathway from Streptomyces alboniger was subcloned as a 13-kilobase fragment in plasmid pIJ702 and expressed in an apparently regulated manner in the heterologous host Streptomyces lividans. The sequencing of a 9.1-kilobase DNA fragment completed the sequence of pur. This permitted identification of seven new open reading frames in the order: napH, pur7, pur10, pur6, pur4, pur5, and pur3. The latter is followed by the known pac, dmpM, and pur8 genes. Nine open reading frames are transcribed rightward as a unit in opposite direction to that of the pur8 gene which is expressed as a monocistronic transcript from the rightmost end. napH encodes the known N-acetylpuromycin N-acetylhydrolase. The deduced products from other open reading frames present similarities to: NTP pyrophosphohydrolases (pur7), several oxidoreductases (pur10), the putative LmbC protein of the lincomycin Biosynthetic Pathway from Streptomyces lincolnensis (pur6), S-adenosylmethionine-dependent methyltransferases (pur5), a variety of presumed aminotransferases (pur4), and several monophosphatases (pur3). According to these similarities and to previous biochemical work, a puromycin Biosynthetic Pathway has been deduced. No cluster-associated regulatory gene was found. However, both pur10 and pur6 genes contain a TTA codon, which suggests that they are translationally controlled by the bldA gene product, a specific tRNALeu.

Guoyin Kai - One of the best experts on this subject based on the ideXlab platform.

  • divergent camptothecin Biosynthetic Pathway in ophiorrhiza pumila
    BMC Biology, 2021
    Co-Authors: Mengquan Yang, Qiang Wang, Yining Liu, Xiaolong Hao, Can Wang, Yuchen Liang, Jianbo Chen, Youli Xiao, Guoyin Kai
    Abstract:

    The anticancer drug camptothecin (CPT), first isolated from Camptotheca acuminata, was subsequently discovered in unrelated plants, including Ophiorrhiza pumila. Unlike known monoterpene indole alkaloids, CPT in C. acuminata is biosynthesized via the key intermediate strictosidinic acid, but how O. pumila synthesizes CPT has not been determined. In this study, we used nontargeted metabolite profiling to show that 3α-(S)-strictosidine and 3-(S), 21-(S)-strictosidinic acid coexist in O. pumila. After identifying the enzymes OpLAMT, OpSLS, and OpSTR as participants in CPT biosynthesis, we compared these enzymes to their homologues from two other representative CPT-producing plants, C. acuminata and Nothapodytes nimmoniana, to elucidate their phylogenetic relationship. Finally, using labelled intermediates to resolve the CPT biosynthesis Pathway in O. pumila, we showed that 3α-(S)-strictosidine, not 3-(S), 21-(S)-strictosidinic acid, is the exclusive intermediate in CPT biosynthesis. In our study, we found that O. pumila, another representative CPT-producing plant, exhibits metabolite diversity in its central intermediates consisting of both 3-(S), 21-(S)-strictosidinic acid and 3α-(S)-strictosidine and utilizes 3α-(S)-strictosidine as the exclusive intermediate in the CPT Biosynthetic Pathway, which differs from C. acuminata. Our results show that enzymes likely to be involved in CPT biosynthesis in O. pumila, C. acuminata, and N. nimmoniana have evolved divergently. Overall, our new data regarding CPT biosynthesis in O. pumila suggest evolutionary divergence in CPT-producing plants. These results shed new light on CPT biosynthesis and pave the way towards its industrial production through enzymatic or metabolic engineering approaches.

  • Divergent camptothecin Biosynthetic Pathway in Ophiorrhiza pumila
    'Springer Science and Business Media LLC', 2021
    Co-Authors: Mengquan Yang, Qiang Wang, Yining Liu, Xiaolong Hao, Can Wang, Yuchen Liang, Jianbo Chen, Youli Xiao, Guoyin Kai
    Abstract:

    Abstract Background The anticancer drug camptothecin (CPT), first isolated from Camptotheca acuminata, was subsequently discovered in unrelated plants, including Ophiorrhiza pumila. Unlike known monoterpene indole alkaloids, CPT in C. acuminata is biosynthesized via the key intermediate strictosidinic acid, but how O. pumila synthesizes CPT has not been determined. Results In this study, we used nontargeted metabolite profiling to show that 3α-(S)-strictosidine and 3-(S), 21-(S)-strictosidinic acid coexist in O. pumila. After identifying the enzymes OpLAMT, OpSLS, and OpSTR as participants in CPT biosynthesis, we compared these enzymes to their homologues from two other representative CPT-producing plants, C. acuminata and Nothapodytes nimmoniana, to elucidate their phylogenetic relationship. Finally, using labelled intermediates to resolve the CPT biosynthesis Pathway in O. pumila, we showed that 3α-(S)-strictosidine, not 3-(S), 21-(S)-strictosidinic acid, is the exclusive intermediate in CPT biosynthesis. Conclusions In our study, we found that O. pumila, another representative CPT-producing plant, exhibits metabolite diversity in its central intermediates consisting of both 3-(S), 21-(S)-strictosidinic acid and 3α-(S)-strictosidine and utilizes 3α-(S)-strictosidine as the exclusive intermediate in the CPT Biosynthetic Pathway, which differs from C. acuminata. Our results show that enzymes likely to be involved in CPT biosynthesis in O. pumila, C. acuminata, and N. nimmoniana have evolved divergently. Overall, our new data regarding CPT biosynthesis in O. pumila suggest evolutionary divergence in CPT-producing plants. These results shed new light on CPT biosynthesis and pave the way towards its industrial production through enzymatic or metabolic engineering approaches

Jianguo Zeng - One of the best experts on this subject based on the ideXlab platform.

  • systematic identification of alkaloids in macleaya microcarpa fruits by liquid chromatography tandem mass spectrometry combined with the isoquinoline alkaloids Biosynthetic Pathway
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Zhixing Qing, Pi Cheng, Xiubin Liu, Yisong Liu, Jianguo Zeng
    Abstract:

    Abstract Alkaloids in Macleaya microcarpa were characterized systematically by combining liquid chromatography tandem mass spectrometry (LC–MS/MS) with the Biosynthetic Pathway of isoquinoline alkaloids. The mass spectral fragmentation behaviors of 16 references belonging to eight types of alkaloids that exist in the Biosynthetic Pathway of isoquinoline were investigated in detail. The benzyltetrahydroisoquinoline and aporphine alkaloids were distinguished by characteristic losses of the NHR 1 R 2 (R 1 and R 2 represent the substituent groups of the nitrogen atom) radical and the fragment ions below m / z 200. Tetrahydroprotoberberine, N -methyltetrahydroberberine and protopine alkaloids were differentiated by the retro-Diels–Alder (RDA) reaction, α-cleavage and the [M–H 2 O] + and [M–CH 4 ] + ions. Discrimination of protoberberine, benzophenanthridine and dihydrobenzophenanthridine-type alkaloids can be realized through the characteristic [fragment ion-2H] + , [M–H 2 O] + , [M–CH 4 ] + , [M+H–CH 3 CH 2 CH 2 OH] + and [M+H–CH 3 COCH 3 ] + ions. Forty-one alkaloids, including one benzyltetrahydroisoquinoline, one aporphine, nine protopines, seven protoberberines, one tetrahydroprotoberberine, three N -methyltetrahydroprotoberberines, five benzophenanthridines and fourteen dihydrobenzophenanthridines, were separated and identified simultaneously. Thirty-three of these were reported for the first time in M. microcarpa . The benzyltetrahydroisoquinoline, aporphine, tetrahydroprotoberberine and N -methyltetrahydroprotoberberine-type alkaloids have not been reported previously in M. microcarpa . This method can be applied to the analysis of herbal medicines that possess the Biosynthetic Pathway of isoquinoline alkaloids.

Song Qin - One of the best experts on this subject based on the ideXlab platform.

Daisuke Umeno - One of the best experts on this subject based on the ideXlab platform.

  • nonnatural Biosynthetic Pathway for 2 hydroxylated xanthophylls with c50 carotenoid backbone
    Journal of Bioscience and Bioengineering, 2019
    Co-Authors: Maiko Furubayashi, Yusuke Otani, Kyoichi Saito, Norihiko Misawa, Takashi Maoka, Shigeko Kawainoma, Daisuke Umeno
    Abstract:

    Carotenoids are structurally diverse pigments with various important biological functions. There has been a large interest in the search for novel carotenoid structures, since only a slight structural changes can result in a drastic difference in their biological functions. Carotenoid-modifying enzymes show remarkable substrate promiscuity, allowing rapid access to a vast set of novel carotenoids by combinatorial biosynthesis. We previously constructed a nonnatural carotenoid Biosynthetic Pathway in Escherichia coli that can produce C50 carotenoids having a longer chain than their natural C40 counterparts. In this study, a carotenoid 2,2'-hydroxylase (crtG) from Brevundimonas sp. SD212 was coexpressed together with our laboratory-engineered C50-zeaxanthin and C50-astaxanthin Biosynthetic Pathways. We identified six novel nonnatural C50-xanthophylls, namely, C50-nostoxanthin, C50-caloxanthin, C50-adonixanthin, C50-4-ketonostoxanthin, C50-2-hydroxyastaxanthin, and C50-2,2′-dihydroxyastaxanthin.