Solution Structure, Determined by Nuclear Magnetic Resonance, of the b30-82 Domain of Subunit b of Escherichia coli F1Fo ATP Synthase

ABSTRACT Subunit b, the peripheral stalk of bacterial F1Fo ATP synthases, is composed of a membrane-spanning and a soluble part. The soluble part is divided into tether, dimerization, and δ-binding domains. The first solution structure of b30-82, including the tether region and part of the dimerization domain, has been solved by nuclear magnetic resonance, revealing an α-helix between residues 39 and 72. In the solution structure, b30-82 has a length of 48.07 Å. The surface charge distribution of b30-82 shows one side with a hydrophobic surface pattern, formed by alanine residues. Alanine residues 61, 68, 70, and 72 were replaced by single cysteines in the soluble part of subunit b, b22-156. The cysteines at positions 61, 68, and 72 showed disulfide formation. In contrast, no cross-link could be formed for the A70C mutant. The patterns of disulfide bonding, together with the circular dichroism spectroscopy data, are indicative of an adjacent arrangement of residues 61, 68, and 72 in both α-helices in b22-156.

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Human Macrophage Inflammatory Protein 3α: Protein and Peptide Nuclear Magnetic Resonance Solution Structures, Dimerization, Dynamics, and Anti-Infective Properties

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00805-07 ◽

2007 ◽

Vol 52 (3) ◽

pp. 883-894 ◽

Cited By ~ 18

Author(s):

David I. Chan ◽

Howard N. Hunter ◽

Brian F. Tack ◽

Hans J. Vogel

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Crystal Structures ◽

Solution Structure ◽

Proton Nuclear Magnetic Resonance ◽

Human Macrophage ◽

Inflammatory Protein ◽

Α Helix ◽

Macrophage Inflammatory Protein ◽

Nuclear Magnetic

ABSTRACT Human macrophage inflammatory protein 3α (MIP-3α), also known as CCL20, is a 70-amino-acid chemokine which exclusively binds to chemokine receptor 6. In addition, the protein also has direct antimicrobial, antifungal, and antiviral activities. The solution structure of MIP-3α was solved by the use of two-dimensional homonuclear proton nuclear magnetic resonance (NMR). The structure reveals the characteristic chemokine fold, with three antiparallel β strands followed by a C-terminal α helix. In contrast to the crystal structures of MIP-3α, the solution structure was found to be monomeric. Another difference between the NMR and crystal structures lies in the angle of the α helix with respect to the β strands, which measure 69 and ∼56.5° in the two structures, respectively. NMR diffusion and pH titration studies revealed a distinct tendency for MIP-3α to form dimers at neutral pH and monomers at lower pH, dependent on the protonation state of His40. Molecular dynamics simulations of both the monomeric and the dimeric forms of MIP-3α supported the notion that the chemokine undergoes a change in helix angle upon dimerization and also highlighted the important hydrophobic and hydrogen bonding contacts made by His40 in the dimer interface. Moreover, a constrained N terminus and a smaller binding groove were observed in dimeric MIP-3α simulations, which could explain why monomeric MIP-3α may be more adept at receptor binding and activation. The solution structure of a synthetic peptide consisting of the last 20 residues of MIP-3α displayed a highly amphipathic α helix, reminiscent of various antimicrobial peptides. Antimicrobial assays with this peptide revealed strong and moderate bactericidal activities against Escherichia coli and Staphylococcus aureus, respectively. This confirms that the C-terminal α-helical region of MIP-3α plays a significant part in its broad anti-infective activity.

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Nuclear magnetic resonance solution structure of Pisum sativum defensin 2 provides evidence for the presence of hydrophobic surface‐clusters

Proteins Structure Function and Bioinformatics ◽

10.1002/prot.25783 ◽

2019 ◽

Vol 88 (1) ◽

pp. 242-246 ◽

Cited By ~ 2

Author(s):

Ramon Pinheiro‐Aguiar ◽

Virginia S. G. do Amaral ◽

Iuri B. Pereira ◽

Eleonora Kurtenbach ◽

Fabio C. L. Almeida

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Pisum Sativum ◽

Solution Structure ◽

Hydrophobic Surface ◽

Resonance Solution ◽

Nuclear Magnetic

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Solution structure of a fragment of the dimerization domain of DP-1 determined by 1H-nuclear magnetic resonance and distance geometry

Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology ◽

10.1016/s0167-4838(98)00208-8 ◽

1998 ◽

Vol 1429 (1) ◽

pp. 18-28

Author(s):

Shouhong Guang ◽

Jihui Wu ◽

Tianning Yu ◽

Youlin Xia ◽

Yunyu Shi

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Solution Structure ◽

Distance Geometry ◽

Dimerization Domain ◽

1H Nuclear Magnetic Resonance ◽

Nuclear Magnetic

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The Solution Structure of YbcJ from Escherichia coli Reveals a Recently Discovered αL Motif Involved in RNA Binding

Journal of Bacteriology ◽

10.1128/jb.185.14.4204-4210.2003 ◽

2003 ◽

Vol 185 (14) ◽

pp. 4204-4210 ◽

Cited By ~ 10

Author(s):

Laurent Volpon ◽

Carine Lievre ◽

Michael J. Osborne ◽

Shaifali Gandhi ◽

Pietro Iannuzzi ◽

...

Keyword(s):

Escherichia Coli ◽

Amino Acids ◽

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Solution Structure ◽

Rna Binding ◽

Bacterial Proteins ◽

Binding Domains ◽

Rna Binding Domains ◽

Nuclear Magnetic

ABSTRACT The structure of the recombinant Escherichia coli protein YbcJ, a representative of a conserved family of bacterial proteins (COG2501), was determined by nuclear magnetic resonance. The fold of YbcJ identified it as a member of the larger family of S4-like RNA binding domains. These domains bind to structured RNA, such as that found in tRNA, rRNA, and a pseudoknot of mRNA. The structure of YbcJ revealed a highly conserved patch of basic residues, comprising amino acids K26, K38, R55, K56, and K59, which likely participate in RNA binding.

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