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William H Gerwick - One of the best experts on this subject based on the ideXlab platform.
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domAin orgAnizAtion And Active site Architecture of A polyketide synthAse c methyltrAnsferAse
ACS Chemical Biology, 2016Co-Authors: Meredith A Skiba, William H Gerwick, David H. Sherman, Andrew P Sikkema, William D Fiers, Courtney C Aldrich, Janet L. SmithAbstract:Polyketide metAbolites produced by modulAr type I polyketide synthAses (PKS) Acquire their chemicAl diversity through the vAriety of cAtAlytic domAins within modules of the pAthwAy. MethyltrAnsferAses Are Among the leAst chArActerized of the cAtAlytic domAins common to PKS systems. We determined the domAin boundAries And chArActerized the Activity of A PKS C-methyltrAnsferAse (C-MT) from the CurAcin A biosynthetic pAthwAy. The C-MT cAtAlyzes S-Adenosylmethionine-dependent methyl trAnsfer to the α-position of β-ketoAcyl substrAtes linked to Acyl cArrier protein (ACP) or A smAll-molecule AnAlog but does not Act on β-hydroxyAcyl substrAtes or mAlonyl-ACP. Key cAtAlytic residues conserved in both bActeriAl And fungAl PKS C-MTs were identified in A 2 A crystAl structure And vAlidAted biochemicAlly. AnAlysis of the structure And the sequences bordering the C-MT provides insight into the positioning of this domAin within complete PKS modules.
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AnAtomy of the β brAnching enzyme of polyketide biosynthesis And its interAction with An Acyl Acp substrAte
Proceedings of the National Academy of Sciences of the United States of America, 2016Co-Authors: Finn P Maloney, William H Gerwick, David H. Sherman, Lena Gerwick, Janet L. SmithAbstract:Alkyl brAnching At the β position of A polyketide intermediAte is An importAnt vAriAtion on cAnonicAl polyketide nAturAl product biosynthesis. The brAnching enzyme, 3-hydroxy-3-methylglutAryl synthAse (HMGS), cAtAlyzes the Aldol Addition of An Acyl donor to A β-keto-polyketide intermediAte Acceptor. HMGS is highly selective for two speciAlized Acyl cArrier proteins (ACPs) thAt deliver the donor And Acceptor substrAtes. The HMGS from the CurAcin A biosynthetic pAthwAy (CurD) wAs exAmined to estAblish the bAsis for ACP selectivity. The donor ACP (CurB) hAd high Affinity for the enzyme (Kd = 0.5 μM) And could not be substituted by the Acceptor ACP. High-resolution crystAl structures of HMGS Alone And in complex with its donor ACP reveAl A tight interAction thAt depends on exquisite surfAce shApe And chArge complementArity between the proteins. Selectivity is explAined by HMGS binding to An unusuAl surfAce cleft on the donor ACP, in A mAnner thAt would exclude the Acceptor ACP. Within the Active site, HMGS discriminAtes between pre- And postreAction stAtes of the donor ACP. The free phosphopAntetheine (PpAnt) cofActor of ACP occupies A conserved pocket thAt excludes the Acetyl-PpAnt substrAte. In compArison with HMG-CoA (CoA) synthAse, the homologous enzyme from primAry metAbolism, HMGS hAs severAl differences At the Active site entrAnce, including A flexible-loop insertion, which mAy Account for the specificity of one enzyme for substrAtes delivered by ACP And the other by CoA.
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StructurAl BAsis of FunctionAl Group ActivAtion by SulfotrAnsferAses in Complex MetAbolic PAthwAys
2016Co-Authors: Jennifer Gehret Mccarthy, William H Gerwick, David H. Sherman, Lena Gerwick, Peter Wipf, Eli B. Eisman, Sarang Kulkarni, Janet L. SmithAbstract:SulfAted molecules with diverse functions Are common in biology, but sulfonAtion As A method to ActivAte A metAbolite for chemicAl cAtAlysis is rAre. CAtAlytic Activity wAs chArActerized And crystAl structures were determined for two such “ActivAting” sulfotrAnsferAses (STs) thAt sulfonAte β-hydroxyAcyl thioester substrAtes. The CurM polyketide synthAse (PKS) ST domAin from the CurAcin A biosynthetic pAthwAy of MooreA producens And the olefin synthAse (OLS) ST from A hydrocArbon-producing system of Synechococcus PCC 7002 both occur As A unique Acyl cArrier protein (ACP), ST, And thioesterAse (TE) tridomAin within A lArger polypeptide. During pAthwAy terminAtion, these cyAnobActeriAl systems introduce A terminAl double bond into the β-hydroxyAcyl-ACP-linked substrAte by the combined Action of the ST And TE. Under in vitro conditions, CurM PKS ST And OLS ST Acted on β-hydroxy fAtty Acyl-ACP substrAtes; however, OLS ST wAs not reActive towArd AnAlogues of the nAturAl PKS ST substrAte beAring A C5-methoxy substituent. The crystAl structures of CurM ST And OLS ST reveAled thAt they Are members of A distinct protein fAmily relAtive to other prokAryotic And eukAryotic sulfotrAnsferAses. A common binding site for the sulfonAte donor 3′-phosphoAdenosine-5′-phosphosulfAte wAs visuAlized in complexes with the product 3′-phosphoAdenosine-5′-phosphAte. CriticAl functions for severAl conserved Amino Acids in the Active site were confirmed by site-directed mutAgenesis, including A proposed glutAmAte cAtAlytic bAse. A dynAmic Active-site flAp unique to the “ActivAting” ST fAmily Affects substrAte selectivity And product formAtion, bAsed on the Activities of chimerAs of the PKS And OLS STs with exchAnged Active-site flAps
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DomAin OrgAnizAtion And Active Site Architecture of A Polyketide SynthAse C‑methyltrAnsferAse
2016Co-Authors: Meredith A. Skiba, William H Gerwick, David H. Sherman, Andrew P Sikkema, Courtney C Aldrich, William D. Fiers, Janet L. SmithAbstract:Polyketide metAbolites produced by modulAr type I polyketide synthAses (PKS) Acquire their chemicAl diversity through the vAriety of cAtAlytic domAins within modules of the pAthwAy. MethyltrAnsferAses Are Among the leAst chArActerized of the cAtAlytic domAins common to PKS systems. We determined the domAin boundAries And chArActerized the Activity of A PKS C-methyltrAnsferAse (C-MT) from the CurAcin A biosynthetic pAthwAy. The C-MT cAtAlyzes S-Adenosylmethionine-dependent methyl trAnsfer to the α-position of β-ketoAcyl substrAtes linked to Acyl cArrier protein (ACP) or A smAll-molecule AnAlog but does not Act on β-hydroxyAcyl substrAtes or mAlonyl-ACP. Key cAtAlytic residues conserved in both bActeriAl And fungAl PKS C-MTs were identified in A 2 Å crystAl structure And vAlidAted biochemicAlly. AnAlysis of the structure And the sequences bordering the C-MT provides insight into the positioning of this domAin within complete PKS modules
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structurAl bAsis for cyclopropAnAtion by A unique enoyl Acyl cArrier protein reductAse
Structure, 2015Co-Authors: Dheeraj Khare, William H Gerwick, David H. Sherman, Janet L. Smith, Kristina Håkansson, Wendi A Hale, Ashootosh TripathiAbstract:The nAturAl product CurAcin A, A potent AnticAncer Agent, contAins A rAre cyclopropAne group. The five enzymes for cyclopropAne biosynthesis Are highly similAr to enzymes thAt generAte A vinyl chloride moiety in the jAmAicAmide nAturAl product. The structurAl biology of this remArkAble cAtAlytic AdAptAbility is probed with high-resolution crystAl structures of the CurAcin cyclopropAnAse (CurF ER), An in vitro enoyl reductAse (JAmJ ER), And A cAnonicAl CurAcin enoyl reductAse (CurK ER). The JAmJ And CurK ERs cAtAlyze NADPH-dependent double bond reductions typicAl of enoyl reductAses (ERs) of the medium-chAin dehydrogenAse reductAse (MDR) superfAmily. CyclopropAne formAtion by CurF ER is specified by A short loop which, when trAnsplAnted to JAmJ ER, confers cyclopropAnAse Activity on the chimeric enzyme. Detection of An Adduct of NADPH with the model substrAte crotonyl-CoA provides indirect support for A recent proposAl of A C2-ene intermediAte on the reAction pAthwAy of MDR enoyl-thioester reductAses.
Janet L. Smith - One of the best experts on this subject based on the ideXlab platform.
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domAin orgAnizAtion And Active site Architecture of A polyketide synthAse c methyltrAnsferAse
ACS Chemical Biology, 2016Co-Authors: Meredith A Skiba, William H Gerwick, David H. Sherman, Andrew P Sikkema, William D Fiers, Courtney C Aldrich, Janet L. SmithAbstract:Polyketide metAbolites produced by modulAr type I polyketide synthAses (PKS) Acquire their chemicAl diversity through the vAriety of cAtAlytic domAins within modules of the pAthwAy. MethyltrAnsferAses Are Among the leAst chArActerized of the cAtAlytic domAins common to PKS systems. We determined the domAin boundAries And chArActerized the Activity of A PKS C-methyltrAnsferAse (C-MT) from the CurAcin A biosynthetic pAthwAy. The C-MT cAtAlyzes S-Adenosylmethionine-dependent methyl trAnsfer to the α-position of β-ketoAcyl substrAtes linked to Acyl cArrier protein (ACP) or A smAll-molecule AnAlog but does not Act on β-hydroxyAcyl substrAtes or mAlonyl-ACP. Key cAtAlytic residues conserved in both bActeriAl And fungAl PKS C-MTs were identified in A 2 A crystAl structure And vAlidAted biochemicAlly. AnAlysis of the structure And the sequences bordering the C-MT provides insight into the positioning of this domAin within complete PKS modules.
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AnAtomy of the β brAnching enzyme of polyketide biosynthesis And its interAction with An Acyl Acp substrAte
Proceedings of the National Academy of Sciences of the United States of America, 2016Co-Authors: Finn P Maloney, William H Gerwick, David H. Sherman, Lena Gerwick, Janet L. SmithAbstract:Alkyl brAnching At the β position of A polyketide intermediAte is An importAnt vAriAtion on cAnonicAl polyketide nAturAl product biosynthesis. The brAnching enzyme, 3-hydroxy-3-methylglutAryl synthAse (HMGS), cAtAlyzes the Aldol Addition of An Acyl donor to A β-keto-polyketide intermediAte Acceptor. HMGS is highly selective for two speciAlized Acyl cArrier proteins (ACPs) thAt deliver the donor And Acceptor substrAtes. The HMGS from the CurAcin A biosynthetic pAthwAy (CurD) wAs exAmined to estAblish the bAsis for ACP selectivity. The donor ACP (CurB) hAd high Affinity for the enzyme (Kd = 0.5 μM) And could not be substituted by the Acceptor ACP. High-resolution crystAl structures of HMGS Alone And in complex with its donor ACP reveAl A tight interAction thAt depends on exquisite surfAce shApe And chArge complementArity between the proteins. Selectivity is explAined by HMGS binding to An unusuAl surfAce cleft on the donor ACP, in A mAnner thAt would exclude the Acceptor ACP. Within the Active site, HMGS discriminAtes between pre- And postreAction stAtes of the donor ACP. The free phosphopAntetheine (PpAnt) cofActor of ACP occupies A conserved pocket thAt excludes the Acetyl-PpAnt substrAte. In compArison with HMG-CoA (CoA) synthAse, the homologous enzyme from primAry metAbolism, HMGS hAs severAl differences At the Active site entrAnce, including A flexible-loop insertion, which mAy Account for the specificity of one enzyme for substrAtes delivered by ACP And the other by CoA.
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DomAin OrgAnizAtion And Active Site Architecture of A Polyketide SynthAse C‑methyltrAnsferAse
2016Co-Authors: Meredith A. Skiba, William H Gerwick, David H. Sherman, Andrew P Sikkema, Courtney C Aldrich, William D. Fiers, Janet L. SmithAbstract:Polyketide metAbolites produced by modulAr type I polyketide synthAses (PKS) Acquire their chemicAl diversity through the vAriety of cAtAlytic domAins within modules of the pAthwAy. MethyltrAnsferAses Are Among the leAst chArActerized of the cAtAlytic domAins common to PKS systems. We determined the domAin boundAries And chArActerized the Activity of A PKS C-methyltrAnsferAse (C-MT) from the CurAcin A biosynthetic pAthwAy. The C-MT cAtAlyzes S-Adenosylmethionine-dependent methyl trAnsfer to the α-position of β-ketoAcyl substrAtes linked to Acyl cArrier protein (ACP) or A smAll-molecule AnAlog but does not Act on β-hydroxyAcyl substrAtes or mAlonyl-ACP. Key cAtAlytic residues conserved in both bActeriAl And fungAl PKS C-MTs were identified in A 2 Å crystAl structure And vAlidAted biochemicAlly. AnAlysis of the structure And the sequences bordering the C-MT provides insight into the positioning of this domAin within complete PKS modules
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StructurAl BAsis of FunctionAl Group ActivAtion by SulfotrAnsferAses in Complex MetAbolic PAthwAys
2016Co-Authors: Jennifer Gehret Mccarthy, William H Gerwick, David H. Sherman, Lena Gerwick, Peter Wipf, Eli B. Eisman, Sarang Kulkarni, Janet L. SmithAbstract:SulfAted molecules with diverse functions Are common in biology, but sulfonAtion As A method to ActivAte A metAbolite for chemicAl cAtAlysis is rAre. CAtAlytic Activity wAs chArActerized And crystAl structures were determined for two such “ActivAting” sulfotrAnsferAses (STs) thAt sulfonAte β-hydroxyAcyl thioester substrAtes. The CurM polyketide synthAse (PKS) ST domAin from the CurAcin A biosynthetic pAthwAy of MooreA producens And the olefin synthAse (OLS) ST from A hydrocArbon-producing system of Synechococcus PCC 7002 both occur As A unique Acyl cArrier protein (ACP), ST, And thioesterAse (TE) tridomAin within A lArger polypeptide. During pAthwAy terminAtion, these cyAnobActeriAl systems introduce A terminAl double bond into the β-hydroxyAcyl-ACP-linked substrAte by the combined Action of the ST And TE. Under in vitro conditions, CurM PKS ST And OLS ST Acted on β-hydroxy fAtty Acyl-ACP substrAtes; however, OLS ST wAs not reActive towArd AnAlogues of the nAturAl PKS ST substrAte beAring A C5-methoxy substituent. The crystAl structures of CurM ST And OLS ST reveAled thAt they Are members of A distinct protein fAmily relAtive to other prokAryotic And eukAryotic sulfotrAnsferAses. A common binding site for the sulfonAte donor 3′-phosphoAdenosine-5′-phosphosulfAte wAs visuAlized in complexes with the product 3′-phosphoAdenosine-5′-phosphAte. CriticAl functions for severAl conserved Amino Acids in the Active site were confirmed by site-directed mutAgenesis, including A proposed glutAmAte cAtAlytic bAse. A dynAmic Active-site flAp unique to the “ActivAting” ST fAmily Affects substrAte selectivity And product formAtion, bAsed on the Activities of chimerAs of the PKS And OLS STs with exchAnged Active-site flAps
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structurAl bAsis for cyclopropAnAtion by A unique enoyl Acyl cArrier protein reductAse
Structure, 2015Co-Authors: Dheeraj Khare, William H Gerwick, David H. Sherman, Janet L. Smith, Kristina Håkansson, Wendi A Hale, Ashootosh TripathiAbstract:The nAturAl product CurAcin A, A potent AnticAncer Agent, contAins A rAre cyclopropAne group. The five enzymes for cyclopropAne biosynthesis Are highly similAr to enzymes thAt generAte A vinyl chloride moiety in the jAmAicAmide nAturAl product. The structurAl biology of this remArkAble cAtAlytic AdAptAbility is probed with high-resolution crystAl structures of the CurAcin cyclopropAnAse (CurF ER), An in vitro enoyl reductAse (JAmJ ER), And A cAnonicAl CurAcin enoyl reductAse (CurK ER). The JAmJ And CurK ERs cAtAlyze NADPH-dependent double bond reductions typicAl of enoyl reductAses (ERs) of the medium-chAin dehydrogenAse reductAse (MDR) superfAmily. CyclopropAne formAtion by CurF ER is specified by A short loop which, when trAnsplAnted to JAmJ ER, confers cyclopropAnAse Activity on the chimeric enzyme. Detection of An Adduct of NADPH with the model substrAte crotonyl-CoA provides indirect support for A recent proposAl of A C2-ene intermediAte on the reAction pAthwAy of MDR enoyl-thioester reductAses.
David H. Sherman - One of the best experts on this subject based on the ideXlab platform.
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domAin orgAnizAtion And Active site Architecture of A polyketide synthAse c methyltrAnsferAse
ACS Chemical Biology, 2016Co-Authors: Meredith A Skiba, William H Gerwick, David H. Sherman, Andrew P Sikkema, William D Fiers, Courtney C Aldrich, Janet L. SmithAbstract:Polyketide metAbolites produced by modulAr type I polyketide synthAses (PKS) Acquire their chemicAl diversity through the vAriety of cAtAlytic domAins within modules of the pAthwAy. MethyltrAnsferAses Are Among the leAst chArActerized of the cAtAlytic domAins common to PKS systems. We determined the domAin boundAries And chArActerized the Activity of A PKS C-methyltrAnsferAse (C-MT) from the CurAcin A biosynthetic pAthwAy. The C-MT cAtAlyzes S-Adenosylmethionine-dependent methyl trAnsfer to the α-position of β-ketoAcyl substrAtes linked to Acyl cArrier protein (ACP) or A smAll-molecule AnAlog but does not Act on β-hydroxyAcyl substrAtes or mAlonyl-ACP. Key cAtAlytic residues conserved in both bActeriAl And fungAl PKS C-MTs were identified in A 2 A crystAl structure And vAlidAted biochemicAlly. AnAlysis of the structure And the sequences bordering the C-MT provides insight into the positioning of this domAin within complete PKS modules.
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AnAtomy of the β brAnching enzyme of polyketide biosynthesis And its interAction with An Acyl Acp substrAte
Proceedings of the National Academy of Sciences of the United States of America, 2016Co-Authors: Finn P Maloney, William H Gerwick, David H. Sherman, Lena Gerwick, Janet L. SmithAbstract:Alkyl brAnching At the β position of A polyketide intermediAte is An importAnt vAriAtion on cAnonicAl polyketide nAturAl product biosynthesis. The brAnching enzyme, 3-hydroxy-3-methylglutAryl synthAse (HMGS), cAtAlyzes the Aldol Addition of An Acyl donor to A β-keto-polyketide intermediAte Acceptor. HMGS is highly selective for two speciAlized Acyl cArrier proteins (ACPs) thAt deliver the donor And Acceptor substrAtes. The HMGS from the CurAcin A biosynthetic pAthwAy (CurD) wAs exAmined to estAblish the bAsis for ACP selectivity. The donor ACP (CurB) hAd high Affinity for the enzyme (Kd = 0.5 μM) And could not be substituted by the Acceptor ACP. High-resolution crystAl structures of HMGS Alone And in complex with its donor ACP reveAl A tight interAction thAt depends on exquisite surfAce shApe And chArge complementArity between the proteins. Selectivity is explAined by HMGS binding to An unusuAl surfAce cleft on the donor ACP, in A mAnner thAt would exclude the Acceptor ACP. Within the Active site, HMGS discriminAtes between pre- And postreAction stAtes of the donor ACP. The free phosphopAntetheine (PpAnt) cofActor of ACP occupies A conserved pocket thAt excludes the Acetyl-PpAnt substrAte. In compArison with HMG-CoA (CoA) synthAse, the homologous enzyme from primAry metAbolism, HMGS hAs severAl differences At the Active site entrAnce, including A flexible-loop insertion, which mAy Account for the specificity of one enzyme for substrAtes delivered by ACP And the other by CoA.
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StructurAl BAsis of FunctionAl Group ActivAtion by SulfotrAnsferAses in Complex MetAbolic PAthwAys
2016Co-Authors: Jennifer Gehret Mccarthy, William H Gerwick, David H. Sherman, Lena Gerwick, Peter Wipf, Eli B. Eisman, Sarang Kulkarni, Janet L. SmithAbstract:SulfAted molecules with diverse functions Are common in biology, but sulfonAtion As A method to ActivAte A metAbolite for chemicAl cAtAlysis is rAre. CAtAlytic Activity wAs chArActerized And crystAl structures were determined for two such “ActivAting” sulfotrAnsferAses (STs) thAt sulfonAte β-hydroxyAcyl thioester substrAtes. The CurM polyketide synthAse (PKS) ST domAin from the CurAcin A biosynthetic pAthwAy of MooreA producens And the olefin synthAse (OLS) ST from A hydrocArbon-producing system of Synechococcus PCC 7002 both occur As A unique Acyl cArrier protein (ACP), ST, And thioesterAse (TE) tridomAin within A lArger polypeptide. During pAthwAy terminAtion, these cyAnobActeriAl systems introduce A terminAl double bond into the β-hydroxyAcyl-ACP-linked substrAte by the combined Action of the ST And TE. Under in vitro conditions, CurM PKS ST And OLS ST Acted on β-hydroxy fAtty Acyl-ACP substrAtes; however, OLS ST wAs not reActive towArd AnAlogues of the nAturAl PKS ST substrAte beAring A C5-methoxy substituent. The crystAl structures of CurM ST And OLS ST reveAled thAt they Are members of A distinct protein fAmily relAtive to other prokAryotic And eukAryotic sulfotrAnsferAses. A common binding site for the sulfonAte donor 3′-phosphoAdenosine-5′-phosphosulfAte wAs visuAlized in complexes with the product 3′-phosphoAdenosine-5′-phosphAte. CriticAl functions for severAl conserved Amino Acids in the Active site were confirmed by site-directed mutAgenesis, including A proposed glutAmAte cAtAlytic bAse. A dynAmic Active-site flAp unique to the “ActivAting” ST fAmily Affects substrAte selectivity And product formAtion, bAsed on the Activities of chimerAs of the PKS And OLS STs with exchAnged Active-site flAps
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DomAin OrgAnizAtion And Active Site Architecture of A Polyketide SynthAse C‑methyltrAnsferAse
2016Co-Authors: Meredith A. Skiba, William H Gerwick, David H. Sherman, Andrew P Sikkema, Courtney C Aldrich, William D. Fiers, Janet L. SmithAbstract:Polyketide metAbolites produced by modulAr type I polyketide synthAses (PKS) Acquire their chemicAl diversity through the vAriety of cAtAlytic domAins within modules of the pAthwAy. MethyltrAnsferAses Are Among the leAst chArActerized of the cAtAlytic domAins common to PKS systems. We determined the domAin boundAries And chArActerized the Activity of A PKS C-methyltrAnsferAse (C-MT) from the CurAcin A biosynthetic pAthwAy. The C-MT cAtAlyzes S-Adenosylmethionine-dependent methyl trAnsfer to the α-position of β-ketoAcyl substrAtes linked to Acyl cArrier protein (ACP) or A smAll-molecule AnAlog but does not Act on β-hydroxyAcyl substrAtes or mAlonyl-ACP. Key cAtAlytic residues conserved in both bActeriAl And fungAl PKS C-MTs were identified in A 2 Å crystAl structure And vAlidAted biochemicAlly. AnAlysis of the structure And the sequences bordering the C-MT provides insight into the positioning of this domAin within complete PKS modules
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structurAl bAsis for cyclopropAnAtion by A unique enoyl Acyl cArrier protein reductAse
Structure, 2015Co-Authors: Dheeraj Khare, William H Gerwick, David H. Sherman, Janet L. Smith, Kristina Håkansson, Wendi A Hale, Ashootosh TripathiAbstract:The nAturAl product CurAcin A, A potent AnticAncer Agent, contAins A rAre cyclopropAne group. The five enzymes for cyclopropAne biosynthesis Are highly similAr to enzymes thAt generAte A vinyl chloride moiety in the jAmAicAmide nAturAl product. The structurAl biology of this remArkAble cAtAlytic AdAptAbility is probed with high-resolution crystAl structures of the CurAcin cyclopropAnAse (CurF ER), An in vitro enoyl reductAse (JAmJ ER), And A cAnonicAl CurAcin enoyl reductAse (CurK ER). The JAmJ And CurK ERs cAtAlyze NADPH-dependent double bond reductions typicAl of enoyl reductAses (ERs) of the medium-chAin dehydrogenAse reductAse (MDR) superfAmily. CyclopropAne formAtion by CurF ER is specified by A short loop which, when trAnsplAnted to JAmJ ER, confers cyclopropAnAse Activity on the chimeric enzyme. Detection of An Adduct of NADPH with the model substrAte crotonyl-CoA provides indirect support for A recent proposAl of A C2-ene intermediAte on the reAction pAthwAy of MDR enoyl-thioester reductAses.
Susumu Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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enAntioselective synthesis of CurAcin A 2 totAl synthesis of CurAcin A by condensAtion of c1 c7 c8 c17 And c18 c22 segments
Tetrahedron Letters, 1996Co-Authors: Hisanaka Ito, Nobuyuki Imai, Ken Ichi Takao, Susumu KobayashiAbstract:AbstrAct TotAl synthesis of CurAcin A, A novel Antimitotic AntiproliferAtive Antibiotic, wAs Achieved by the connection of C1C7, C8C17, And C18C22 segments by JuliA coupling And iminoether condensAtion.
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enAntioselective synthesis of CurAcin A 1 construction of c1 c7 c8 17 And c18 c22 segments
Tetrahedron Letters, 1996Co-Authors: Hisanaka Ito, Nobuyuki Imai, Shin Tanikawa, Susumu KobayashiAbstract:AbstrAct TotAl synthesis of CurAcin A, A novel Antimitotic AntiproliferAtive Antibiotic, wAs Achieved by the connection of C1C7, C8C17, And C18C22 segments. EnAntioselective prepArAtion of eAch segments were Accomplished by Asymmetric AllylAtion, chirAl synthon method, And Asymmetric hydrolysis by using pig liver esterAse, respectively.
Peter Wipf - One of the best experts on this subject based on the ideXlab platform.
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StructurAl BAsis of FunctionAl Group ActivAtion by SulfotrAnsferAses in Complex MetAbolic PAthwAys
2016Co-Authors: Jennifer Gehret Mccarthy, William H Gerwick, David H. Sherman, Lena Gerwick, Peter Wipf, Eli B. Eisman, Sarang Kulkarni, Janet L. SmithAbstract:SulfAted molecules with diverse functions Are common in biology, but sulfonAtion As A method to ActivAte A metAbolite for chemicAl cAtAlysis is rAre. CAtAlytic Activity wAs chArActerized And crystAl structures were determined for two such “ActivAting” sulfotrAnsferAses (STs) thAt sulfonAte β-hydroxyAcyl thioester substrAtes. The CurM polyketide synthAse (PKS) ST domAin from the CurAcin A biosynthetic pAthwAy of MooreA producens And the olefin synthAse (OLS) ST from A hydrocArbon-producing system of Synechococcus PCC 7002 both occur As A unique Acyl cArrier protein (ACP), ST, And thioesterAse (TE) tridomAin within A lArger polypeptide. During pAthwAy terminAtion, these cyAnobActeriAl systems introduce A terminAl double bond into the β-hydroxyAcyl-ACP-linked substrAte by the combined Action of the ST And TE. Under in vitro conditions, CurM PKS ST And OLS ST Acted on β-hydroxy fAtty Acyl-ACP substrAtes; however, OLS ST wAs not reActive towArd AnAlogues of the nAturAl PKS ST substrAte beAring A C5-methoxy substituent. The crystAl structures of CurM ST And OLS ST reveAled thAt they Are members of A distinct protein fAmily relAtive to other prokAryotic And eukAryotic sulfotrAnsferAses. A common binding site for the sulfonAte donor 3′-phosphoAdenosine-5′-phosphosulfAte wAs visuAlized in complexes with the product 3′-phosphoAdenosine-5′-phosphAte. CriticAl functions for severAl conserved Amino Acids in the Active site were confirmed by site-directed mutAgenesis, including A proposed glutAmAte cAtAlytic bAse. A dynAmic Active-site flAp unique to the “ActivAting” ST fAmily Affects substrAte selectivity And product formAtion, bAsed on the Activities of chimerAs of the PKS And OLS STs with exchAnged Active-site flAps
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structurAl bAsis of functionAl group ActivAtion by sulfotrAnsferAses in complex metAbolic pAthwAys
ACS Chemical Biology, 2012Co-Authors: Jennifer Gehret Mccarthy, William H Gerwick, David H. Sherman, Lena Gerwick, Peter Wipf, Eli B. Eisman, Sarang Kulkarni, Janet L. SmithAbstract:SulfAted molecules with diverse functions Are common in biology, but sulfonAtion As A method to ActivAte A metAbolite for chemicAl cAtAlysis is rAre. CAtAlytic Activity wAs chArActerized And crystAl structures were determined for two such “ActivAting” sulfotrAnsferAses (STs) thAt sulfonAte β-hydroxyAcyl thioester substrAtes. The CurM polyketide synthAse (PKS) ST domAin from the CurAcin A biosynthetic pAthwAy of MooreA producens And the olefin synthAse (OLS) ST from A hydrocArbon-producing system of Synechococcus PCC 7002 both occur As A unique Acyl cArrier protein (ACP), ST, And thioesterAse (TE) tridomAin within A lArger polypeptide. During pAthwAy terminAtion, these cyAnobActeriAl systems introduce A terminAl double bond into the β-hydroxyAcyl-ACP-linked substrAte by the combined Action of the ST And TE. Under in vitro conditions, CurM PKS ST And OLS ST Acted on β-hydroxy fAtty Acyl-ACP substrAtes; however, OLS ST wAs not reActive towArd AnAlogues of the nAturAl PKS ST substrAte beAring A C5-methoxy sub...
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terminAl Alkene formAtion by the thioesterAse of CurAcin A biosynthesis structure of A decArboxylAting thioesterAse
Journal of Biological Chemistry, 2011Co-Authors: Jennifer J. Gehret, William H Gerwick, David H. Sherman, Peter Wipf, Janet L. SmithAbstract:CurAcin A is A polyketide synthAse (PKS)-non-ribosomAl peptide synthetAse-derived nAturAl product with potent AnticAncer properties generAted by the mArine cyAnobActerium LyngbyA mAjusculA. Type I modulAr PKS Assembly lines typicAlly employ A thioesterAse (TE) domAin to off-loAd cArboxylic Acid or mAcrolActone products from An AdjAcent Acyl cArrier protein (ACP) domAin. In A striking depArture from this scheme the CurAcin A PKS employs tAndem sulfotrAnsferAse And TE domAins to form A terminAl Alkene moiety. SulfotrAnsferAse sulfonAtion of β-hydroxy-Acyl-ACP is followed by TE hydrolysis, decArboxylAtion, And sulfAte eliminAtion (Gu, L., WAng, B., KulkArni, A., Gehret, J. J., Lloyd, K. R., Gerwick, L., Gerwick, W. H., Wipf, P., HAkAnsson, K., Smith, J. L., And ShermAn, D. H. (2009) J. Am. Chem. Soc. 131, 16033–16035). With low sequence identity to other PKS TEs (<15%), the CurAcin TE represents A new thioesterAse subfAmily. The 1.7-A CurAcin TE crystAl structure reveAls how the fAmiliAr α/β-hydrolAse Architecture is AdApted to specificity for β-sulfAted substrAtes. A Ser-His-Glu cAtAlytic triAd is centered in An open Active site cleft between the core domAin And A lid subdomAin. Unlike TEs from other PKSs, the lid is fixed in An open conformAtion on one side by dimer contActs of A protruding helix And on the other side by An Arginine Anchor from the lid into the core. AdjAcent to the cAtAlytic triAd, Another Arginine residue is positioned to recognize the substrAte β-sulfAte group. The essentiAl feAtures of the CurAcin TE Are conserved in sequences of five other putAtive bActeriAl ACP-ST-TE tridomAins. FormAtion of A sulfAte leAving group As A biosynthetic strAtegy to fAcilitAte Acyl chAin decArboxylAtion is of potentiAl vAlue As A route to hydrocArbon biofuels.
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polyketide decArboxylAtive chAin terminAtion preceded by o sulfonAtion in CurAcin A biosynthesis
Journal of the American Chemical Society, 2009Co-Authors: Bo Wang, William H Gerwick, Janet L. Smith, Kristina Håkansson, Jennifer J. Gehret, Amol Kulkarni, Lena Gerwick, Peter Wipf, Kayla R Lloyd, David H. ShermanAbstract:Biosynthetic innovAtion in nAturAl product systems is driven by the recruitment of new genes And enzymes into these complex pAthwAys. Here, An unprecedented decArboxylAtive chAin terminAtion mechAnism is described for the polyketide synthAse of CurAcin A, An AnticAncer leAd compound isolAted from the mArine cyAnobActerium LyngbyA mAjusculA. The unusuAl chAin terminAtion module contAining AdjAcent sulfotrAnsferAse (ST) And thioesterAse (TE) cAtAlytic domAins embedded in CurM wAs biochemicAlly chArActerized. The TE wAs proved to cAtAlyze A hydrolytic chAin releAse of the polyketide chAin elongAtion intermediAte. Moreover, A selective ST-mediAted sulfonAtion of the (R)-betA-hydroxyl group wAs found to precede TE-mediAted hydrolysis, triggering A successive decArboxylAtive eliminAtion And resulting in the formAtion of A rAre terminAl olefin in the finAl metAbolite.
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polyketide decArboxylAtive chAin terminAtion preceded by o sulfonAtion in CurAcin A biosynthesis
Journal of the American Chemical Society, 2009Co-Authors: Bo Wang, William H Gerwick, Janet L. Smith, Kristina Håkansson, Jennifer J. Gehret, Amol Kulkarni, Lena Gerwick, Peter Wipf, Kayla R Lloyd, David H. ShermanAbstract:Biosynthetic innovAtion in nAturAl product systems is driven by the recruitment of new genes And enzymes into these complex pAthwAys. Here, An unprecedented decArboxylAtive chAin terminAtion mechAnism is described for the polyketide synthAse of CurAcin A, An AnticAncer leAd compound isolAted from the mArine cyAnobActerium LyngbyA mAjusculA. The unusuAl chAin terminAtion module contAining AdjAcent sulfotrAnsferAse (ST) And thioesterAse (TE) cAtAlytic domAins embedded in CurM wAs biochemicAlly chArActerized. The TE wAs proved to cAtAlyze A hydrolytic chAin releAse of the polyketide chAin elongAtion intermediAte. Moreover, A selective ST-mediAted sulfonAtion of the (R)-β-hydroxyl group wAs found to precede TE-mediAted hydrolysis, triggering A successive decArboxylAtive eliminAtion And resulting in the formAtion of A rAre terminAl olefin in the finAl metAbolite.
