Secondary structure of Escherichia coli glucosamine-6-phosphate deaminase from amino acid sequence and circular dichroism spectroscopy

Physical studies on the effect of temperature and ionic conditions on the secondary, tertiary, and quaternary structure of the ribosomal "A" protein, equivalent to L7/L12 in Escherichia coli, from two archaebacteria were performed using circular dichroism and sedimentation equilibrium measurements. The two archaebacteria investigated were Halobacterium cutirubrum, an extreme halophile, and Methanobacterium thermoautotrophicum, a thermophile which also showed properties of a moderate halophile. The changes in the secondary structure and the thermostability of these proteins were directly related to the internal salt concentrations of the two archaebacteria. At the higher salt concentrations the changes in the secondary structure resulted in changes in the tertiary and quaternary structure of these proteins.

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Circular dichroism studies of sheep β-lipotropic hormone

Canadian Journal of Biochemistry ◽

10.1139/o76-143 ◽

1976 ◽

Vol 54 (11) ◽

pp. 992-998 ◽

Cited By ~ 14

Author(s):

Serge St-Pierre ◽

Claude Gilardeau ◽

Michel Chrétien

Keyword(s):

Circular Dichroism ◽

Amino Acid ◽

Amino Acid Sequence ◽

Conformational Transition ◽

Acidic Solutions ◽

Nacl Concentration ◽

Helical Content ◽

The Stability ◽

Far Ultraviolet ◽

Circular Dichroïsm

The far ultraviolet circular dichroism spectra of sheep β-lipotropic hormone (β-LPH) were recorded under different conditions of pH, temperature, salt concentration, and solvent composition. Results confirm the stability of the hormone in strong basic or acidic solutions; moreover, temperatures up to 50 °C do not seem to affect noticeably the conformation of β-LPH. However, increasing the NaCl concentration or addition of dioxane in the solution brings about a conformational transition of the chain, interpreted as an increase in the helical content. The method of Yang (Chen, Y. H., Yang, J. T. &Martinez, H. M. (1972) Biochemistry 11, 4120–4131) was used to compute the proportion of helical, β, and unordered forms of the hormone chain. The proportions are compared with those obtained from Fasman's predictive method (Chou, P. Y. &Fasman, G. D. (1974) Biochemistry 13, 211–221 and Chou, P. Y. &Fasman, G. D. (1974) Biochemistry 13, 222–245) based on the known amino acid sequence of β-LPH.

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Circular dichroism spectroscopy has intrinsic limitations for protein secondary structure analysis

Analytical Biochemistry ◽

10.1016/j.ab.2009.03.036 ◽

2009 ◽

Vol 389 (2) ◽

pp. 174-176 ◽

Cited By ~ 24

Author(s):

Sergei Khrapunov

Keyword(s):

Circular Dichroism ◽

Secondary Structure ◽

Structure Analysis ◽

Protein Secondary Structure ◽

Circular Dichroism Spectroscopy ◽

Secondary Structure Analysis ◽

Circular Dichroïsm

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Water-soluble lysine-containing polypeptides. IV. The synthesis, characterization,and circular dichroism spectra of sequential polypeptides formed from dipeptides of lysine and amino acids of increasing side chain size

Canadian Journal of Chemistry ◽

10.1139/v77-603 ◽

1977 ◽

Vol 55 (24) ◽

pp. 4257-4266 ◽

Cited By ~ 2

Author(s):

Lewis A. Slotin ◽

Denis R. Lauren ◽

Ross E. Williams

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Circular Dichroism ◽

Secondary Structure ◽

Gel Filtration ◽

Circular Dichroism Spectroscopy ◽

Water Soluble ◽

Side Chain ◽

Circular Dichroism Spectra ◽

Circular Dichroïsm

Several polypeptides have been synthesized which contain the alternating sequence lysyl-X, where X = gly, L-ala, D-ala, L-val, L-leu, and L-phe. The polypeptides have been characterized by gel filtration (molecular weight) and by circular dichroism spectroscopy (secondary structure).

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