+ Translate
+ Most Popular
The pigeon tick (Argas reflexus): its biology, ecology, and epidemiological aspects
Prevalence of hemoglobin abnormalities in Kebili (Tunisian South)
Lipogranuloma: a preventable complication of dacryocystorhinostomy
Value of basal plasma cortisol assays in the assessment of pituitary-adrenal insufficiency
Bees from the Belgian Congo. The acraensis group of Anthophora
Placing gingival retraction cord
Total serum IgE, allergy skin testing, and the radioallergosorbent test for the diagnosis of allergy in asthmatic children
Acariens plumicoles Analgesoidea parasites des oiseaux du Maroc
Injuries of terminal phalanges of the fingers in children
Biology of flowering and nectar production in pear (Pyrus communis)
Das Reliktvorkommen der Aspisviper (Vipera aspis L.) im Schwarzwald
Hydrological modelling of drained blanket peatland
Pathologic morphology and clinical significance of the anomalous origin of the left circumflex coronary artery from the right coronary artery. General review and autopsy analysis of 30 cases
Cyto genetic analyses of lymphocyte cultures after exposure to calcium cyclamate
Axelrodia riesei, a new characoid fish from Upper Rio Meta in Colombia With remarks concerning the genus Axelrodia and description of a similar, sympatric, Hyphessobrycon-species
Favorable evolution of a case of tuberculosis of pancreas under antibiotic action
RIFM fragrance ingredient safety assessment, Valencene, CAS Registry Number 4630-07-3
Parenteral microemulsions: an overview
Temperate pasture: management for grazing and conservation
Evaluation of a new coprocessed compound based on lactose and maize starch for tablet formulation
Thermal expansion and cracking of three confined water-saturated igneous rocks to 800C
Revision of the genera of the tribe Stigmoderini (Coleoptera: Buprestidae) a discussion of phylogenetic relationships
Anal tuberculosis. Report of a case
Gastric tuberculosis in the past and present
Adaptive responses of the cardiovascular system to prolonged spaceflight conditions: assessment with Holter monitoring

Vibrational Raman optical activity of alpha-lactalbumin: comparison with lysozyme, and evidence for native tertiary folds in molten globule states

Vibrational Raman optical activity of alpha-lactalbumin: comparison with lysozyme, and evidence for native tertiary folds in molten globule states

Journal of Molecular Biology 254(4): 747-760

ISSN/ISBN: 0022-2836

PMID: 7500347

DOI: 10.1006/jmbi.1995.0652

Proteins in aqueous solution are now accessible to Raman optical activity (ROA) measurements, which provide an incisive new probe of secondary and tertiary structure illustrated here by a study of bovine alpha-lactalbumin. The room-temperature ROA spectrum of native bovine alpha-lactalbumin is similar to that of native hen egg-white lysozyme except for features attributable to differences in the loop regions: in particular, a positive ROA band at approximately 1338 cm-1 assigned to conformationally homogeneous loop structure, possibly with local order corresponding to 3(10)-helix, has more than double the intensity in alpha-lactalbumin compared with lysozyme. This is consistent with the two proteins having similar secondary structure but different local details in the tertiary fold. ROA measurements on alpha-lactalbumin at pH 2.0 over a range of temperatures have provided a new perspective on the molten globule state. Thus at 35 degrees C ROA reveals the presence of some secondary structure but an almost complete loss of the tertiary loop structure; whereas at 2 degrees C the ROA spectrum is almost identical with that of the native protein, which is strong evidence that virtually all of the secondary structure and the tertiary backbone fold persist, albeit within a looser framework associated with increased solvent exposure and change of environment of many of the side-chains as evidenced by an increase in noise and bandwidth of some of the ROA signals together with aromatic fluorescence and near-UV circular dichroism signals characteristic of the molten globule state. Our sample of acid alpha-lactalbumin at 2 degrees C therefore appears to be an archetypal example of Ptitsyn's "native-like" molten globule, having a fixed native-like tertiary fold but with loss of tight packing of the side-chains; whereas at 35 degrees C it is a "disordered" molten globule. At 20 degrees C the acid molten globule appears to retain highly native-like secondary structure but with most of the tertiary fold already lost. A calcium-free sample of alpha-lactalbumin at neutral pH displayed a broad cooperative transition between native and molten globule states at approximately 15 degrees C, with the latter state showing similar but somewhat degraded tertiary loop ROA signatures to the native protein. In both the acid and apo molten globule states the ROA signatures of the secondary structure and the tertiary loops showed a gradual change with temperature.

Please choose payment method:

(PDF emailed within 0-6 h: $19.90)

Accession: 009723835

Download citation: RISBibTeXText

Related references

Vibrational Raman optical activity of a-lactalbumin: comparison with lysozyme, and evidence for native tertiary folds in molten globule states. Journal of Molecular Biology 254: 7-60, 1995

Raman optical activity characterization of native and molten globule states of equine lysozyme: comparison with hen lysozyme and bovine alpha-lactalbumin. Biopolymers 57(4): 235-248, 2000

Comparison of intramolecular packings in human alpha -lactalbumin in native and molten globule states. Studia Biophysica 112(2/3): 207-211, 1986

Quasielastic light scattering from human alpha lactalbumin comparison of molecular dimensions in native and molten globule states. International Journal of Biological Macromolecules 8(4): 231-236, 1986

Determinants of the native-like tertiary topology in the alpha-lactalbumin molten globule. Kuwajima, Kunihiro Author, Arai, Munehito Author International Congress Series; Old and new views of protein folding 145-154, 1999

Contribution of individual residues to formation of the native-like tertiary topology in the alpha-lactalbumin molten globule. Journal of Molecular Biology 280(1): 167-174, 1998

Action of protein-glutaminase on alpha-lactalbumin in the native and molten globule states. Journal of Agricultural and Food Chemistry 49(12): 5999-6005, 2001

Non two-state denaturing transition from native to molten globule states of apo-alpha-lactalbumin. Biophysical Journal 72(2 Part 2): A394, 1997

Direct measurement of the energetics of the molten globule and native states of alpha lactalbumin. Biophysical Journal 61(2 Part 2): A477, 1992

The native-like tertiary fold in molten globule alpha-lactalbumin appears to be controlled by a continuous phase transition. Journal of Molecular Biology 261(3): 341-347, 1996

Contribution of the 6-120 disulfide bond of alpha-lactalbumin to the stabilities of its native and molten globule states. Biochemistry 31(50): 12695-12700, 1992

Rotational diffusion studies of native and molten globule states of bovine alpha lactalbumin. Studia Biophysica 126(2): 87-97, 1988

Modulation of stability of the native and molten globule states of alpha-lactalbumin by site-specific mutagenesis. FASEB Journal 8(7): A1386, 1994

Different subdomains are most protected from hydrogen exchange in the molten globule and native states of human alpha-lactalbumin. Journal of Molecular Biology 253(5): 651-657, 1995

Enzymatic digestion and antioxidant activity of the native and molten globule states of camel -lactalbumin possible significance for use in infant formula. International Dairy Journal 19(9): 0-523, 2009