Effects of peripheral substituents on diastereoselectivity of the fifth ligand-binding to chlorophylls, and nomenclature of the asymmetric axial coordination sites

Oba, Toru; Tamiaki, Hitoshi

doi:10.1016/j.bmc.2005.06.016

Cited by 33 publications

(19 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the folded conformer of zinc Chl derivative dyads, the central zinc atoms were coordinated by a methanol molecule as an axial ligand to give a five‐coordinated species. It is known that the chlorin π ‐plane of Chl derivatives has two faces, α ‐ and β ‐faces . In the folded conformer, the five‐coordinated zinc took either α ‐ or β ‐ligation and four stereoisomers are proposed for the coordination sites, α , α ‐, α , β ‐, β , α ‐ and β , β ‐ligation (see Fig.…”

Section: Resultsmentioning

confidence: 99%

Synthesis of Zinc Chlorophyll Homo/Hetero‐Dyads and their Folded Conformers with Porphyrin, Chlorin, and Bacteriochlorin π‐Systems

Tamiaki

Fukai

Shimazu

et al. 2013

Photochem & Photobiology

Self Cite

View full text Add to dashboard Cite

Zinc complex of pyropheophorbide-b, a derivative of chlorophyll-b, was covalently dimerized through ethylene glycol diester. The synthetic homo-dyad was axially ligated with two methanol molecules from the β-face and both the diastereomerically coordinating methanol species were hydrogen bonded with the keto-carbonyl groups of the neighboring chlorin in a complex. The resulting folded conformer in a solution was confirmed by visible, (1) H NMR and IR spectra. All the synthetic zinc chlorin homo- and hetero-dyads consisting of pyropheophorbides-a, b and/or d took the above methanol-locked and π-π stacked supramolecules in 1% (v/v) methanol and benzene to give redmost (Qy) electronic absorption band(s) at longer wavelengths than those of the corresponding monomeric chlorin composites. The other zinc chlorin and bacteriochlorin homo-dyads completely formed similar folded conformers in the same solution, while zinc inverse chlorin and porphyrin homo-dyads partially took such supramolecules. The J-type aggregation to folded conformers and the redshift values of composite Qy bands were dependent on the electronic and steric factors of porphyrinoid moieties in dyads.

show abstract

Section: Resultsmentioning

confidence: 99%

Synthesis of Zinc Chlorophyll Homo/Hetero‐Dyads and their Folded Conformers with Porphyrin, Chlorin, and Bacteriochlorin π‐Systems

Tamiaki

Fukai

Shimazu

et al. 2013

Photochem & Photobiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…X‐ray crystallographic analyses of (B)Chl–protein complexes (see references cited in Ref. 42) showed the presence of such interaction and also intermolecular interaction of phytyl groups under restricted environments. One reason why phytyl esters are exclusively used in (B)Chl molecules inside photosynthetic proteins might be that branched chains are superior to straight chains for the above hydrophobic interactions.…”

Section: Discussionmentioning

confidence: 99%

The 17‐Propionate Function of (Bacterio)chlorophylls: Biological Implication of Their Long Esterifying Chains in Photosynthetic Systems^†

Tamiaki

Shibata

Mizoguchi

2007

Photochem & Photobiology

Self Cite

193

105

View full text Add to dashboard Cite

Molecular structures of (bacterio)chlorophylls [=(B)Chls] in photosynthetic apparatus are surveyed, and a diversity of the ester groups of the 17-propionate substituent is particularly focused on in this review. In oxygenic photosynthetic species including green plants and algae, the ester of Chl molecules is limited to a phytyl group. Geranylgeranyl and farnesyl groups in addition to phytyl are observed in (B)Chl molecules inside photosynthetic proteins of anoxygenic bacteria. In main lightharvesting antennas of green bacteria (chlorosomes), a greater variety of ester groups including long straight chains are used in the composite BChl molecules. This diversity is ascribable to the fact that chlorosomal BChls self-aggregate to form a core part of chlorosomes without any specific interaction of oligopeptides. Biological significance of the long chains is discussed in photosynthetic apparatus, especially in chlorosomes.

show abstract

“…For the bacterial RC II this has already resulted in the unambiguous identification of "conserved" chlorophyll conformations for the different functional classes of cofactors [281] and a similar analysis of the bacterial LHC is warranted [282]. Another example is the diastereoselectivity of the axial ligand binding in chlorophylls, which has now been confirmed using data from PS II and LHCII [283].…”

Section: Discussionmentioning

confidence: 59%

Chlorophylls, Symmetry, Chirality, and Photosynthesis

et al. 2014

View full text Add to dashboard Cite

Chlorophylls are a fundamental class of tetrapyrroles and function as the central reaction center, accessory and photoprotective pigments in photosynthesis. Their unique individual photochemical properties are a consequence of the tetrapyrrole macrocycle, the structural chemistry and coordination behavior of the phytochlorin system, and specific substituent pattern. They achieve their full potential in solar energy conversion by working in concert in highly complex, supramolecular structures such as the reaction centers and light-harvesting complexes of photobiology. The biochemical function of these structures depends on the controlled interplay of structural and functional principles of the apoprotein and pigment cofactors. Chlorophylls and bacteriochlorophylls are optically active molecules with several chiral centers, which are necessary for their natural biological function and the assembly of their supramolecular complexes. However, in many cases the exact role of chromophore stereochemistry in the biological context is unknown. This review gives an overview of chlorophyll research in terms of basic function, biosynthesis and their functional and structural role in photosynthesis. It highlights aspects of chirality and symmetry of chlorophylls to elicit further interest in their role in nature.

show abstract

Effects of peripheral substituents on diastereoselectivity of the fifth ligand-binding to chlorophylls, and nomenclature of the asymmetric axial coordination sites

Cited by 33 publications

References 31 publications

Synthesis of Zinc Chlorophyll Homo/Hetero‐Dyads and their Folded Conformers with Porphyrin, Chlorin, and Bacteriochlorin π‐Systems

Synthesis of Zinc Chlorophyll Homo/Hetero‐Dyads and their Folded Conformers with Porphyrin, Chlorin, and Bacteriochlorin π‐Systems

The 17‐Propionate Function of (Bacterio)chlorophylls: Biological Implication of Their Long Esterifying Chains in Photosynthetic Systems^†

Chlorophylls, Symmetry, Chirality, and Photosynthesis

Contact Info

Product

Resources

About

Effects of peripheral substituents on diastereoselectivity of the fifth ligand-binding to chlorophylls, and nomenclature of the asymmetric axial coordination sites

Cited by 33 publications

References 31 publications

Synthesis of Zinc Chlorophyll Homo/Hetero‐Dyads and their Folded Conformers with Porphyrin, Chlorin, and Bacteriochlorin π‐Systems

Synthesis of Zinc Chlorophyll Homo/Hetero‐Dyads and their Folded Conformers with Porphyrin, Chlorin, and Bacteriochlorin π‐Systems

The 17‐Propionate Function of (Bacterio)chlorophylls: Biological Implication of Their Long Esterifying Chains in Photosynthetic Systems†

Chlorophylls, Symmetry, Chirality, and Photosynthesis

Contact Info

Product

Resources

About

The 17‐Propionate Function of (Bacterio)chlorophylls: Biological Implication of Their Long Esterifying Chains in Photosynthetic Systems^†