Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803
The cyclase step in chlorophyll (Chl) biosynthesis has not been characterized biochemically, although there are some plausible candidates for cyclase subunits. Two of these, Sll1214 and Sll1874 from the cyanobacterium Synechocystis 6803, were FLAG-tagged in vivo and used as bait in separate pulldown...
Main Authors: | , , , , , , , |
---|---|
Format: | Journal article |
Published: |
American Society for Biochemistry and Molecular Biology
2012
|
_version_ | 1826282264777981952 |
---|---|
author | Hollingshead, S Kopecna, J Jackson, P Canniffe, D Davison, P Dickman, M Sobotka, R Hunter, C |
author_facet | Hollingshead, S Kopecna, J Jackson, P Canniffe, D Davison, P Dickman, M Sobotka, R Hunter, C |
author_sort | Hollingshead, S |
collection | OXFORD |
description | The cyclase step in chlorophyll (Chl) biosynthesis has not been characterized biochemically, although there are some plausible candidates for cyclase subunits. Two of these, Sll1214 and Sll1874 from the cyanobacterium Synechocystis 6803, were FLAG-tagged in vivo and used as bait in separate pulldown experiments. Mass spectrometry identified Ycf54 as an interaction partner in each case, and this interaction was confirmed by a reciprocal pulldown using FLAG-tagged Ycf54 as bait. Inactivation of the ycf54 gene (slr1780) in Synechocystis 6803 resulted in a strain that exhibited significantly reduced Chl levels. A detailed analysis of Chl precursors in the ycf54 mutant revealed accumulation of very high levels of Mg-protoporphyrin IX methyl ester and only traces of protochlorophyllide, the product of the cyclase, were detected. Western blotting demonstrated that levels of the cyclase component Sll1214 and the Chl biosynthesis enzymes Mg-protoporphyrin IX methyltransferase and protochlorophyllide reductase are significantly impaired in the ycf54 mutant. Ycf54 is, therefore, essential for the activity and stability of the oxidative cyclase. We discuss a possible role of Ycf54 as an auxiliary factor essential for the assembly of a cyclase complex or even a large multienzyme catalytic center. |
first_indexed | 2024-03-07T00:41:13Z |
format | Journal article |
id | oxford-uuid:8318d1a6-b75f-4852-9db5-abb43e357dbc |
institution | University of Oxford |
last_indexed | 2024-03-07T00:41:13Z |
publishDate | 2012 |
publisher | American Society for Biochemistry and Molecular Biology |
record_format | dspace |
spelling | oxford-uuid:8318d1a6-b75f-4852-9db5-abb43e357dbc2022-03-26T21:41:58ZConserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:8318d1a6-b75f-4852-9db5-abb43e357dbcSymplectic Elements at OxfordAmerican Society for Biochemistry and Molecular Biology2012Hollingshead, SKopecna, JJackson, PCanniffe, DDavison, PDickman, MSobotka, RHunter, CThe cyclase step in chlorophyll (Chl) biosynthesis has not been characterized biochemically, although there are some plausible candidates for cyclase subunits. Two of these, Sll1214 and Sll1874 from the cyanobacterium Synechocystis 6803, were FLAG-tagged in vivo and used as bait in separate pulldown experiments. Mass spectrometry identified Ycf54 as an interaction partner in each case, and this interaction was confirmed by a reciprocal pulldown using FLAG-tagged Ycf54 as bait. Inactivation of the ycf54 gene (slr1780) in Synechocystis 6803 resulted in a strain that exhibited significantly reduced Chl levels. A detailed analysis of Chl precursors in the ycf54 mutant revealed accumulation of very high levels of Mg-protoporphyrin IX methyl ester and only traces of protochlorophyllide, the product of the cyclase, were detected. Western blotting demonstrated that levels of the cyclase component Sll1214 and the Chl biosynthesis enzymes Mg-protoporphyrin IX methyltransferase and protochlorophyllide reductase are significantly impaired in the ycf54 mutant. Ycf54 is, therefore, essential for the activity and stability of the oxidative cyclase. We discuss a possible role of Ycf54 as an auxiliary factor essential for the assembly of a cyclase complex or even a large multienzyme catalytic center. |
spellingShingle | Hollingshead, S Kopecna, J Jackson, P Canniffe, D Davison, P Dickman, M Sobotka, R Hunter, C Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 |
title | Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 |
title_full | Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 |
title_fullStr | Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 |
title_full_unstemmed | Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 |
title_short | Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 |
title_sort | conserved chloroplast open reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis pcc 6803 |
work_keys_str_mv | AT hollingsheads conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT kopecnaj conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT jacksonp conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT canniffed conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT davisonp conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT dickmanm conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT sobotkar conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 AT hunterc conservedchloroplastopenreadingframeycf54isrequiredforactivityofthemagnesiumprotoporphyrinmonomethylesteroxidativecyclaseinsynechocystispcc6803 |