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Molecular identification of an ABC transporter complex for manganese: analysis of a cyanobacterial mutant strain impaired in the photosynthetic oxygen evolution process.

1995; Springer Nature; Volume: 14; Issue: 9 Linguagem: Inglês

10.1002/j.1460-2075.1995.tb07176.x

1460-2075

Victor V. Bartsevich, Himadri B. Pakrasi,

Trace Elements in Health

Research Article1 May 1995free access Molecular identification of an ABC transporter complex for manganese: analysis of a cyanobacterial mutant strain impaired in the photosynthetic oxygen evolution process. V.V. Bartsevich V.V. Bartsevich Department of Biology, Washington University, St Louis, MO 63130, USA. Search for more papers by this author H.B. Pakrasi H.B. Pakrasi Department of Biology, Washington University, St Louis, MO 63130, USA. Search for more papers by this author V.V. Bartsevich V.V. Bartsevich Department of Biology, Washington University, St Louis, MO 63130, USA. Search for more papers by this author H.B. Pakrasi H.B. Pakrasi Department of Biology, Washington University, St Louis, MO 63130, USA. Search for more papers by this author Author Information V.V. Bartsevich1 and H.B. Pakrasi1 1Department of Biology, Washington University, St Louis, MO 63130, USA. The EMBO Journal (1995)14:1845-1853https://doi.org/10.1002/j.1460-2075.1995.tb07176.x PDFDownload PDF of article text and main figures. ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures & Info During photosynthesis, the photosystem II (PSII) pigment-protein complex catalyzes oxygen evolution, a reaction in which a four-manganese ensemble plays a crucial role. Using a newly developed selection scheme, we have isolated BP13, a random photosynthesis-deficient mutant strain of the cyanobacterium, Synechocystis 6803. This mutant grew slowly under photoautotrophic conditions, and had a low oxygen evolution activity. Biochemical analysis revealed that the lesion in this mutant strain had specifically affected the Mn ensemble in PSII. Interestingly, incubation of BP13 cells with micromolar levels of added Mn induced rapid recovery of oxygen evolution activity. The mutant could be complemented with a fragment of wild-type chromosomal DNA containing three closely linked genes, mntA, mntB and mntC. These gene products showed significant sequence similarities with polypeptide components of bacterial permeases that are members of the 'ABC (ATP binding cassette) superfamily' of transporter proteins. We determined that in the BP13 strain, a single nucleotide change had resulted in the replacement of an alanine by an aspartic acid residue in MntA, a soluble protein containing ATP binding motifs. These results suggest that the mntCAB gene cluster encodes polypeptide components of a Mn transporter, the first such protein complex identified in any organism. Previous ArticleNext Article Volume 14Issue 91 May 1995In this issue RelatedDetailsLoading ...