Lobophorins(LOBs)belong to a large family of spirotetronate antibiotics with antibacterial and antitumor activities.In this study,we demonstrated the function of LobP1,a P450 monooxygenase encoded in the LOB biosynthe...Lobophorins(LOBs)belong to a large family of spirotetronate antibiotics with antibacterial and antitumor activities.In this study,we demonstrated the function of LobP1,a P450 monooxygenase encoded in the LOB biosynthetic gene cluster,by in vivo deletion and in vitro biochemical assays.The disruption of lobP1 led to the isolation of three new LOBs derivatives(3-5)and three known ones(6-8)without the hydroxyl group at C-32.LobP1 was shown to have relatively broad substrate scope.Determining the kinetic parameters of LobP1 towards different substrates revealed that LobP1 preferred substrate with a nitrosugar.The new LOBs 3-5 displayed significant antibacterial activities against Bacillus subtilis and Micrococcus luteus with MIC values of 0.125 to 1μg·mL^(-1),and the major product LOB E(6)from the∆lobP1 mutant showed moderate cytotoxic activities against several cancer cell lines.展开更多
Stimuli-responsive molecules are highly desirable in different scenario such as smart materials,bio-imaging,and environment monitoring.Herein,a series of hetero polycycles which show optical response toward chemical s...Stimuli-responsive molecules are highly desirable in different scenario such as smart materials,bio-imaging,and environment monitoring.Herein,a series of hetero polycycles which show optical response toward chemical stimuli are synthesized from trithiasumanene(TTS).The TTS is transformed into ortho-quinone form,which then undergoes three-component Debus-Radziszewski reaction with aldehydes and ammonia to give oxazole-fused TTS(2-6).The thiophene rings on 3-5 are selectively oxidized to thiophene-S,S-dioxides,affording 3-3O_(2)-5-3O_(2).It is found that the electronic structures of these compounds are governed by the sub-stituents on oxazole moiety and oxidation state of thiophene ring.Moreover,these hetero polycycles exhibit optical response toward different chemical stimuli.Particularly,compounds 6 and 3-3O_(2) can serve as fluorescence detectors for harmful chemicals sulfide ions(S2-/HS-)and aniline,respectively.This work indicates that TTS is a promising precursor for the creation of responsive materials.展开更多
基金supported in part by the National Natural Science Foundation of China(22193072 and 32100045)the Key Science and Technology Project of Hainan Province(ZDKJ202018)+4 种基金MOST(2018YFA0901903)K.C.WongEducationnFoundation(GJTD-2020-12)the Guangdong Provincial Special Fund for Marine Economic Development Project(GDNRC[2021]48)the Science and Technology Planning Project of Guangzhou(202102020471)Rising Star Foundation of the South China Sea Institute of Oceanology(NHXX2018SW0201)。
文摘Lobophorins(LOBs)belong to a large family of spirotetronate antibiotics with antibacterial and antitumor activities.In this study,we demonstrated the function of LobP1,a P450 monooxygenase encoded in the LOB biosynthetic gene cluster,by in vivo deletion and in vitro biochemical assays.The disruption of lobP1 led to the isolation of three new LOBs derivatives(3-5)and three known ones(6-8)without the hydroxyl group at C-32.LobP1 was shown to have relatively broad substrate scope.Determining the kinetic parameters of LobP1 towards different substrates revealed that LobP1 preferred substrate with a nitrosugar.The new LOBs 3-5 displayed significant antibacterial activities against Bacillus subtilis and Micrococcus luteus with MIC values of 0.125 to 1μg·mL^(-1),and the major product LOB E(6)from the∆lobP1 mutant showed moderate cytotoxic activities against several cancer cell lines.
基金This work was supported by the National Key R&D Program of China(No.2017YFA0204903)the National Natural Science Foundation of China(No.21871119).
文摘Stimuli-responsive molecules are highly desirable in different scenario such as smart materials,bio-imaging,and environment monitoring.Herein,a series of hetero polycycles which show optical response toward chemical stimuli are synthesized from trithiasumanene(TTS).The TTS is transformed into ortho-quinone form,which then undergoes three-component Debus-Radziszewski reaction with aldehydes and ammonia to give oxazole-fused TTS(2-6).The thiophene rings on 3-5 are selectively oxidized to thiophene-S,S-dioxides,affording 3-3O_(2)-5-3O_(2).It is found that the electronic structures of these compounds are governed by the sub-stituents on oxazole moiety and oxidation state of thiophene ring.Moreover,these hetero polycycles exhibit optical response toward different chemical stimuli.Particularly,compounds 6 and 3-3O_(2) can serve as fluorescence detectors for harmful chemicals sulfide ions(S2-/HS-)and aniline,respectively.This work indicates that TTS is a promising precursor for the creation of responsive materials.
