Mutational analyses of HAMP helices suggest a dynamic bundle model of input-output signalling in chemoreceptors

Mutational analyses of HAMP helices suggest a dynamic bundle model of input-output signalling in chemoreceptors.

To test the gearbox model of HAMP signalling in the Escherichia coli serine receptor, Tsr, we generated a series of amino acid replacements at each residue of the AS1 and AS2 helices. The residues most critical for Tsr function defined hydrophobic packing faces consistent with a four-helix bundle. Suppression patterns of helix lesions conformed to the predicted packing layers in the bundle. Alt...

HAMP domain structural determinants for signalling and sensory adaptation in Tsr, the Escherichia coli serine chemoreceptor.

HAMP domains mediate input-output transactions in many bacterial signalling proteins. To clarify the mechanistic logic of HAMP signalling, we constructed Tsr-HAMP deletion derivatives and characterized their steady-state signal outputs and sensory adaptation properties with flagellar rotation and receptor methylation assays. Tsr molecules lacking the entire HAMP domain or just the HAMP-AS2 heli...

Biphasic control logic of HAMP domain signalling in the Escherichia coli serine chemoreceptor.

HAMP domains mediate input-output communication in many bacterial signalling proteins. To explore the dynamic bundle model of HAMP signalling (Zhou et al., Mol. Microbiol. 73: 801, 2009), we characterized the signal outputs of 118 HAMP missense mutants of the serine chemoreceptor, Tsr, by flagellar rotation patterns. Receptors with proline or charged amino acid replacements at critical hydropho...

ENVIRONMENTAL IMPACTS OF ENERGY-EFFICIENT TECHNOLOGIES: POTENTIAL FOR INPUT-OUTPUT AND SUPPLY-CHAIN ANALYSES IN IRAN

investigating the feasibility of a proposed model for geometric design of deployable arch structures

deployable scissor type structures are composed of the so-called scissor-like elements (sles), which are connected to each other at an intermediate point through a pivotal connection and allow them to be folded into a compact bundle for storage or transport. several sles are connected to each other in order to form units with regular polygonal plan views. the sides and radii of the polygons are...