Mimicking the Function of Eggshell Matrix Proteins: The Role of Multiplets of Charged Amino Acid Residues and Self-Assembly of Peptides in Biomineralization

AbstractThe main goal of this work was to make the cDNA-encoding subunit G2 of soybean glycinin, capable of self-assembly in vitro and rich in methionine residues. Two mutants (pSP65/G4SacG2 and pSP65/G4SacG2HG4) were therefore constructed. The constructed mutants were successfully assembled in vitro into oligomers similar to those occurred in the seed. The successful self-assembly was due to the introduction of Sac fragment of Gy4 (the codons of the first 21 amino acid residues), which reported to be the key element in self-assembly into trimers. The mutant pSP65/G4SacG2HG4 included the acidic chain of Gy4 (HG4), which was previously molecularly modified to have three methionine residues. This mutant will be useful in the efforts to improve the seed quality.

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Chemical Modification of Lysozyme, Glucose 6-Phosphate Dehydrogenase, and Bovine Eye Lens Proteins Induced by Peroxyl Radicals: Role of Oxidizable Amino Acid Residues

Chemical Research in Toxicology ◽

10.1021/tx300372t ◽

2013 ◽

Vol 26 (1) ◽

pp. 67-77 ◽

Cited By ~ 28

Author(s):

Andrea Arenas ◽

Camilo López-Alarcón ◽

Marcelo Kogan ◽

Eduardo Lissi ◽

Michael J. Davies ◽

...

Keyword(s):

Amino Acid ◽

Chemical Modification ◽

Peroxyl Radicals ◽

Eye Lens ◽

Amino Acid Residues ◽

Lens Proteins ◽

Glucose 6 Phosphate Dehydrogenase ◽

Eye Lens Proteins

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Deletion of the Actin-Associated Tropomyosin Tpm3 Leads to Reduced Cell Complexity in Cultured Hippocampal Neurons—New Insights into the Role of the C-Terminal Region of Tpm3.1

Cells ◽

10.3390/cells10030715 ◽

2021 ◽

Vol 10 (3) ◽

pp. 715

Author(s):

Tamara Tomanić ◽

Claire Martin ◽

Holly Stefen ◽

Esmeralda Parić ◽

Peter Gunning ◽

...

Keyword(s):

Amino Acid ◽

Hippocampal Neurons ◽

Molecular Mechanisms ◽

Growth Cones ◽

Amino Acid Residues ◽

Terminal Amino Acid ◽

C Terminus ◽

Primary Mouse ◽

Terminal Amino

Tropomyosins (Tpms) have been described as master regulators of actin, with Tpm3 products shown to be involved in early developmental processes, and the Tpm3 isoform Tpm3.1 controlling changes in the size of neuronal growth cones and neurite growth. Here, we used primary mouse hippocampal neurons of C57/Bl6 wild type and Bl6Tpm3flox transgenic mice to carry out morphometric analyses in response to the absence of Tpm3 products, as well as to investigate the effect of C-terminal truncation on the ability of Tpm3.1 to modulate neuronal morphogenesis. We found that the knock-out of Tpm3 leads to decreased neurite length and complexity, and that the deletion of two amino acid residues at the C-terminus of Tpm3.1 leads to more detrimental changes in neurite morphology than the deletion of six amino acid residues. We also found that Tpm3.1 that lacks the 6 C-terminal amino acid residues does not associate with stress fibres, does not segregate to the tips of neurites, and does not impact the amount of the filamentous actin pool at the axonal growth cones, as opposed to Tpm3.1, which lacks the two C-terminal amino acid residues. Our study provides further insight into the role of both Tpm3 products and the C-terminus of Tpm3.1, and it forms the basis for future studies that aim to identify the molecular mechanisms underlying Tpm3.1 targeting to different subcellular compartments.

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Role of amino acid residues at the interface of α52asparginyl-N-glycosyl chain of human choriogonadotropin

Molecular and Cellular Endocrinology ◽

10.1016/s0303-7207(99)00026-x ◽

1999 ◽

Vol 150 (1-2) ◽

pp. 47-56 ◽

Cited By ~ 1

Author(s):

Kui Shao ◽

Sathyamangalam V. Balasubramanian ◽

Om P. Bahl

Keyword(s):

Amino Acid ◽

Amino Acid Residues ◽

Human Choriogonadotropin

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Assembly of amino acid containing naphthalene diimide-based molecules: the role of intervening amide groups in self-assembly, gelation, optical and semiconducting properties

Soft Matter ◽

10.1039/c8sm02460j ◽

2019 ◽

Vol 15 (14) ◽

pp. 3018-3026 ◽

Cited By ~ 10

Author(s):

Nibedita Nandi ◽

Kousik Gayen ◽

Arindam Banerjee

Keyword(s):

Amino Acid ◽

Self Assembly ◽

Naphthalene Diimide ◽

Semiconducting Properties

Two isomeric amino-acid containing naphthalene diimide based molecules differ in their respective assembly and the intervening amide groups plays an important role in gelation, optical and semiconducting nature of these molecules.

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N-Terminal 33 Amino Acid Residues ofEscherichia coliRecA Protein Contribute to its Self-assembly

Journal of Molecular Biology ◽

10.1006/jmbi.1995.0391 ◽

1995 ◽

Vol 250 (4) ◽

pp. 471-483 ◽

Cited By ~ 30

Author(s):

Tsutomu Mikawa ◽

Ryoji Masui ◽

Tomoko Ogawa ◽

Hideyuki Ogawa ◽

Seiki Kuramitsu

Keyword(s):

Amino Acid ◽

Self Assembly ◽

Amino Acid Residues

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The functional dyad of scorpion toxin Pi1 is not itself a prerequisite for toxin binding to the voltage-gated Kv1.2 potassium channels

Biochemical Journal ◽

10.1042/bj20030115 ◽

2004 ◽

Vol 377 (1) ◽

pp. 25-36 ◽

Cited By ~ 50

Author(s):

Stéphanie MOUHAT ◽

Amor MOSBAH ◽

Violeta VISAN ◽

Heike WULFF ◽

Muriel DELEPIERRE ◽

...

Keyword(s):

Amino Acid ◽

Scorpion Toxin ◽

Xenopus Laevis Oocytes ◽

Amino Acid Residues ◽

Voltage Gated ◽

Toxin Binding ◽

Ic50 Values

Pi1 is a 35-residue scorpion toxin cross-linked by four disulphide bridges that acts potently on both small-conductance Ca2+-activated (SK) and voltage-gated (Kv) K+ channel subtypes. Two approaches were used to investigate the relative contribution of the Pi1 functional dyad (Tyr-33 and Lys-24) to the toxin action: (i) the chemical synthesis of a [A24,A33]-Pi1 analogue, lacking the functional dyad, and (ii) the production of a Pi1 analogue that is phosphorylated on Tyr-33 (P-Pi1). According to molecular modelling, this phosphorylation is expected to selectively impact the two amino acid residues belonging to the functional dyad without altering the nature and three-dimensional positioning of other residues. P-Pi1 was directly produced by peptide synthesis to rule out any possibility of trace contamination by the unphosphorylated product. Both Pi1 analogues were compared with synthetic Pi1 for bioactivity. In vivo, [A24,A33]-Pi1 and P-Pi1 are lethal by intracerebroventricular injection in mice (LD50 values of 100 and 40 µg/mouse, respectively). In vitro, [A24,A33]-Pi1 and P-Pi1 compete with 125I-apamin for binding to SK channels of rat brain synaptosomes (IC50 values of 30 and 10 nM, respectively) and block rat voltage-gated Kv1.2 channels expressed in Xenopus laevis oocytes (IC50 values of 22 µM and 75 nM, respectively), whereas they are inactive on Kv1.1 or Kv1.3 channels at micromolar concentrations. Therefore, although both analogues are less active than Pi1 both in vivo and in vitro, the integrity of the Pi1 functional dyad does not appear to be a prerequisite for the recognition and binding of the toxin to the Kv1.2 channels, thereby highlighting the crucial role of other toxin residues with regard to Pi1 action on these channels. The computed simulations detailing the docking of Pi1 peptides on to the Kv1.2 channels support an unexpected key role of specific basic amino acid residues, which form a basic ring (Arg-5, Arg-12, Arg-28 and Lys-31 residues), in toxin binding.

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