Biochemical importance of the binding of phosphate by arginyl groups.  Model compounds containing methylguanidinium ion

Cotton, F. Albert; Hazen, E. E.; Day, Victor W.; Larsen, S.; Norman, Joanne; Wong, S. T. K.; Johnson, K. H.

doi:10.1021/ja00788a047

Cited by 75 publications

(28 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, we observed that routine reconstitutions of control PT00-Fx cores to form functional PToo--FAFB complexes were unsuccessful if the experiments were conducted using phosphate buffer (data not shown). This is also consistent with the data presented above implicating a domain containing arginine residues in the PsaC reconstitution because it is well known that arginine residues are anion recognition sites in many enzymes (Riordan et al 1977) and that the guanidinium group is well suited for interaction with the phosphate moiety (Cotton et al 1973). Therefore, we suggest that the inability to reconstitute the modified core to form a functional PT00--FAFB complex is most likely because of structural changes in the binding site for PsaC.…”

Section: Discussionsupporting

confidence: 92%

Interaction of the FAFB-containing subunit with the Photosystem 1 core heterodimer

1993

View full text Add to dashboard Cite

The structure of the predicted amino acid sequence in the FX domain of Photosystem 1 was studied by molecular modeling and a working hypothesis was developed for the functional interaction of PsaC with the core heterodimer. We propose that the intervening sequences between homologous cysteines in the FX cluster form two flexible loops and participate in the binding of PsaC, and that the arginine residues in the two surface-exposed loops may promote the interaction between the P700-FX core and the subunit. The model was tested experimentally; chemical modification of arginine residues in the P700-FX core using phenylglyoxal prevented reconstitution of the core with PsaC and PsaD after insertion of FeS clusters in vitro. Treatment of the P700-FX core with trypsin also prevented reconstitution of terminal electron transfer to FAFB, although neither treatments affected the electron transfer to FX as judged by flash kinetic spectrophotometry. Electron transfer in the P700-FAFB complex was not impaired by either phenylglyoxal or trypsin treatment indicating that the small subunit(s) protect the arginine residues that become chemically modified or cleaved. The data are consistent with the working model and point to additional experiments designed to identify the specific residues involved in the interaction between the P700-FX core and PsaC.

show abstract

Section: Discussionsupporting

confidence: 92%

Interaction of the FAFB-containing subunit with the Photosystem 1 core heterodimer

1993

View full text Add to dashboard Cite

show abstract

“…It is known that arginyl phosphate and diarginyl phosphate interactions are prevalent in the active sites of many enzymes, and the structure of these complexes may be predicted based upon the crystallographic study of the model compound dimethylguanidinium phosphate. 13 Therefore, we reasoned that the postulated electrostatic repulsion between PsaC D9R and a positively charged residue in the wild-type core binding site 3 might be "rescued" by the formation of such phosphate complexes. Examples of primary data showing the results of such reconstitutions are presented in Figure 1.…”

Section: Resultsmentioning

confidence: 99%

“…13 The inhibition of reconstitution by both wild type and mutant PsaC subunits at higher concentrations of P i most likely occurs by electrostatic repulsion between a core arginyl phosphate and residue D9 in the case of wild-type PsaC, and D9-arginyl phosphate in the case of the mutant D9R. Figure 3 shows that a similar rescue -TTAACCGTGTTCCTTGGCGCGGCC NRVPWDGC QQ 5′-TTAACCAGGTTCCTTGGCAGGGCC NQVPWQGL SN 5′-TTAACAGCAACAGCAACGATAACC NSNSNDNL AV 5′-TTAACGCAGTTGCAGGTGCAGGTC NAVAGAGL PV 5′-TTAACGCAGTTCCAGGTGCAGGTC NAVPGAGL of reconstitution of PS I cores by PsaC D9R can also be achieved using low concentrations of molybdate as well as P i.…”

Section: Resultsmentioning

confidence: 99%

Protein−Protein Interactions between the Photosystem I Reaction Center Core and the PsaC Subunit

Chiou

Biggins

1998

J. Phys. Chem. B

View full text Add to dashboard Cite

The functional reconstitution of Photosystem I reaction center cores by wild-type and mutant PsaC subunits at high ionic strength indicated that hydrophobic interactions are dominant in stabilizing the reaction center. Deletion of the region E27 through C34 in the PsaC backbone resulted in a mutant subunit with impaired reconstitution, confirming that this segment is required for binding. Restoration of the deletion mutant protein to full length using a series of inserts of graded hydrophobicity, including residues with side chains of various sizes, established that this domain is involved in hydrophobic interactions with the reaction center core. The results indicate that a specific proline residue may be necessary to confer the requisite secondary structure in this domain of the PsaC subunit. The overall data provide additional indirect support for orientation of the PsaC subunit on the reaction center such that the F B cluster is close to the core F X redox center. We also report that an electrostatic interaction between residue D9 of PsaC and a complimentary basic residue in the core binding site is essential, and most likely ensures the correct orientation of the PsaC subunit on the core during assembly of the reaction center. We previously reported that residue R561 of the PsaB core subunit is also involved in an electrostatic interaction and contributes to the stability of Photosytem I [Rodday, S. M.; Schulz, R.; McIntosh, L.; Biggins, J. Photosynth. Res. 1994, 42185]. We report here that this PsaB core residue is not paired with D9 of the PsaC subunit and postulate that it may be involved in a PsaB(A) intracore interaction.

show abstract

“…However, experimental proof is lacking that the inhibition of enzymatic activity by phenylglyoxal is indeed a result of a modification of arginine 419. Arginines are known to be ideally suited for interaction with negatively charged phosphate groups due to their ability to form multiple hydrogen bonds with this moiety (35). Because of resonance stabilization of the guanidinium group in the side chains of these residues, arginines are poor proton donors and would probably not function as general acid catalysts (36).…”

Section: Discussionmentioning

confidence: 99%

Alkyl-Dihydroxyacetonephosphate Synthase

Vet

IJlst²,

Oostheim³

et al. 1998

Journal of Biological Chemistry

109

View full text Add to dashboard Cite

Peroxisomes play an indispensible role in ether lipid biosynthesis as evidenced by the deficiency of ether phospholipids in fibroblasts and tissues from patients suffering from a number of peroxisomal disorders. Alkyl-dihydroxyacetonephosphate synthase, a peroxisomal enzyme playing a key role in the biosynthesis of ether phospholipids, contains the peroxisomal targeting signal type 2 in a N-terminal cleavable presequence. Using a polyclonal antiserum raised against alkyl-dihydroxyacetonephosphate synthase, levels of this enzyme were examined in fibroblast cell lines from patients affected by peroxisomal disorders. Strongly reduced levels were found in fibroblasts of Zellweger syndrome and rhizomelic chondrodysplasia punctata patients, indicating that the enzyme is not stable in the cytoplasm as a result of defective import into peroxisomes. In a neonatal adrenoleukodystrophy patient with an isolated import deficiency of proteins carrying the peroxisomal targeting signal type 1, the precursor form of alkyl-dihydroxyacetonephosphate synthase was detected at a level comparable to that of the mature form in control fibroblasts, in line with an intraperoxisomal localization. A patient with an isolated deficiency in alkyl-dihydroxyacetonephosphate (DHAP) synthase activity had normal levels of this protein. Analysis at the cDNA level revealed a missense mutation leading to a R419H substitution in the enzyme of this patient. Expression of a recombinant protein carrying this mutation in Escherichia coli yielded an inactive enzyme, whereas a comparable control recombinant enzyme was active, providing further proof that this substitution is responsible for the inactivity of the enzyme and the phenotype. In line with this result is the observation that wild-type alkyl-DHAP synthase activity can be inactivated by the arginine-modifying agent phenylglyoxal. The enzyme is efficiently protected against this inactivation when the substrate palmitoyl-DHAP is present at a saturating concentration. The gene encoding human alkyl-dihydroxyacetonephosphate synthase was mapped on chromosome 2q31.

show abstract

Biochemical importance of the binding of phosphate by arginyl groups. Model compounds containing methylguanidinium ion

Cited by 75 publications

References 0 publications

Interaction of the FAFB-containing subunit with the Photosystem 1 core heterodimer

Interaction of the FAFB-containing subunit with the Photosystem 1 core heterodimer

Protein−Protein Interactions between the Photosystem I Reaction Center Core and the PsaC Subunit

Alkyl-Dihydroxyacetonephosphate Synthase

Contact Info

Product

Resources

About