Cytochrome components of green alga, Bryopsis maxima1

Kamímura, Yasumaro; Yamasaki, Takenobu; Matsuzaki, Etsuzo

doi:10.1093/oxfordjournals.pcp.a075437

Cited by 17 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cytochrome c M shows sequence homology with a number of other c ‐type cytochromes, including mitochondrial cytochrome c , Bacillus subtilis cytochrome c 550, and Synechocystis 6803 cytochrome c 6 [2]. Kerfeld and Krogmann [1] discuss cytochrome c M ‐like proteins that have been reported in the past, including high‐potential cytochrome c 549 from the green alga Bryopsis maxima [21], cytochrome c 549 from Scenedesmus obliquus D 3 [22], and cytochrome c 552 from the cyanobacterium Anacystis nidulans [23,24].…”

Section: Discussionmentioning

confidence: 99%

Cytochrome c_M from Synechocystis 6803

Cho¹,

Pakrasi²,

Whitmarsh³

2000

European Journal of Biochemistry

View full text Add to dashboard Cite

Based on DNA sequence data a novel c-type cytochrome, cytochrome c M , has been predicted to exist in the cyanobacterium Synechocystis 6803. The precursor protein consists of 105 amino acids with a characteristic heme-binding motif and a hydrophobic domain located at the N-terminal end that is proposed to act as either a signal peptide or a membrane anchor. For the first time we report the detection of cytochrome c M in Synechocystis 6803 using Western blot analysis. The soluble portion cytochrome c M has been overexpressed in Escherichia coli in two forms, one with a poly histidine tag to facilitate purification and one without such a tag. The overexpressed protein has been purified and shown to bind heme, exhibiting an absorption peak in the Soret band near 416 nm and a peak in the a band at 550 nm. The extinction coefficient of cytochrome c M is 23.2^0.5 mm 21´c m 21 for the reduced minus oxidized a band peak (550±535 nm). The isoelectric point of cytochrome c M is 5.6 (without the histidine tag), which is significantly lower than the pI of 7.2 predicted from the amino acid sequence. The redox midpoint potential of cytochrome c M expressed in E. coli is 151^5 mV (pH 7.1), which is quite low compared to other c-type cytochromes in which a histidine and a methionine residue serve as the axial ligands to the heme. This work opens the way for determining the three-dimensional structure of cytochrome c M and investigating its function in cyanobacteria.

show abstract

Section: Discussionmentioning

confidence: 99%

Cytochrome c_M from Synechocystis 6803

Cho¹,

Pakrasi²,

Whitmarsh³

2000

European Journal of Biochemistry

View full text Add to dashboard Cite

show abstract

“…There is only one article in which cyt c550 has been detected in a green alga (Bryopsis maxima) by a spectrum assigned to this cytochrome [45]. No further confirmation has been 01/11/2011 made by other authors and no cyt c550 protein sequence or psbV gene has been found for any green algae in any of the databases searched.…”

Section: Occurrencementioning

confidence: 97%

Photosynthetic cytochrome c550

Roncel

Kirilovsky

Guerrero

et al. 2012

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

Cytochrome c550 (cyt c550) is a membrane component of the PSII complex in cyanobacteria and some eukaryotic algae, such as red and brown algae. Cyt c550 presents a bis-histidine heme coordination which is very unusual for monoheme c-type cytochromes. In PSII, the cyt c550 with the other extrinsic proteins stabilizes the binding of Cl(-) and Ca(2+) ions to the oxygen evolving complex and protects the Mn(4)Ca cluster from attack by bulk reductants. The role (if there is one) of the heme of the cyt c550 is unknown. The low midpoint redox potential (E(m)) of the purified soluble form (from -250 to -314mV) is incompatible with a redox function in PSII. However, more positive values for the Em have been obtained for the cyt c550 bound to the PSII. A very recent work has shown an E(m) value of +200mV. These data open the possibility of a redox function for this protein in electron transfer in PSII. Despite the long distance (22Å) between cyt c550 and the nearest redox cofactor (Mn(4)Ca cluster), an electron transfer reaction between these components is possible. Some kind of protective cycle involving a soluble redox component in the lumen has also been proposed. The aim of this article is to review previous studies done on cyt c550 and to consider its function in the light of the new results obtained in recent years. The emphasis is on the physical properties of the heme and its redox properties. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial.

show abstract

“…Absorbance peaks are evident at 552.5 (a), 522.5 Cp), 416 ( y or Soret band), 318 (8) and 275 (protein) nm; shoulders at 392, 354 and 289 nm are observed. While most algal cytochromes c6 exhibit an asymmetric a peak [36], the cytochromes of Euglena grucilis [37] and M. braunii are the only two exceptions, having a symmetric a peak. Upon oxidation with ammonium persulfate, the a and p peaks are replaced by a broader absorbance band with a maximum at 528 nm, whereas the Soret band shifts to 410 nm; the band at 318 nm disappears and a new band at 359 nm is observed.…”

Section: Visible Spectramentioning

confidence: 98%

Cytochrome c₆ from Monoraphidium braunii

Campos

Aguiar

Hervás

et al. 1993

European Journal of Biochemistry

View full text Add to dashboard Cite

A soluble monoheme c-type cytochrome (cytochrome c,) has been isolated from the green alga Monoraphidium braunii. It has a molecular mass of 9.3 kDa, an isoelectric point of 3.6 and a reduction potential of 358 mV at pH 7. The determined amino acid sequence allows its classification as a class-I c-type cytochrome. The femc and ferrous cytochrome forms and their pH equilibria have been studied using 'H-NMR, ultraviolet/visible, EPR and Mossbauer spectroscopies. The pH equilibria are complex, several pK, values and pH-dependent forms being observed. The amino acid sequence, the reduction-potential value and the visible and NMR spectroscopies data in the pH range 4-9 indicate that the heme iron has a methionine-histidine axial coordination. However, the EPR and Mossbauer data obtained for the ferricytochrome show that in this pH range two distinct forms are present: form I, g, = 3.27, g, = 2.05 and g, = 1.05; form 11, g, = 2.95, g, = 2.29 and g, = 1.43. While form I has crystal-field parameters typical of a methionine-histidine coordination, those associated with form I1 would suggest a histidine-histidine axial ligation. This possibility was extensively analyzed by spectroscopic methods and by chemical modification of a histidine residue. It was concluded that form I1 actually corresponds to an unusual type of methionine-histidine axial coordination. Straightforward examples of this type of coordination have recently been found in other c-type hemeproteins [

show abstract

Cytochrome components of green alga, Bryopsis maxima1

Cited by 17 publications

References 0 publications

Cytochrome c_M from Synechocystis 6803

Cytochrome c_M from Synechocystis 6803

Photosynthetic cytochrome c550

Cytochrome c₆ from Monoraphidium braunii

Contact Info

Product

Resources

About

Cytochrome components of green alga, Bryopsis maxima1

Cited by 17 publications

References 0 publications

Cytochrome cM from Synechocystis 6803

Cytochrome cM from Synechocystis 6803

Photosynthetic cytochrome c550

Cytochrome c6 from Monoraphidium braunii

Contact Info

Product

Resources

About

Cytochrome c_M from Synechocystis 6803

Cytochrome c_M from Synechocystis 6803

Cytochrome c₆ from Monoraphidium braunii