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Protein & Peptide Letters

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ISSN (Print): 0929-8665
ISSN (Online): 1875-5305

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Research Article

Parakeet Hemoglobin – Its Crystal Structure and Oxygen Affinity in Relation to Some Avian Hemoglobins

Author(s): S.M. Jaimohan*, M.D. Naresh and A.B. Mandal*

Volume 28, Issue 1, 2021

Published on: 20 March, 2020

Page: [18 - 30] Pages: 13

DOI: 10.2174/0929866527666200320100109

Price: $65

Abstract

Background: “Avians” often show efficient oxygen management to meet the demands of their metabolism. Hemoglobin, a transporter protein consists of four non-covalently linked subunits contain haem binding hydrophobic pocket serves as a site of allosteric cooperativity. The physiology and anatomy of both mammals and avian are functionally different, in birds, the respiratory system formed by small air sacs that serve as tidal ventilation for the lungs and have no significant exchange across their cells. Parakeet (Psittacula krameri) a tropical and non-migrating species and it is easily adapted to living in disturbed habitat. The sequence analysis reveals that α and β chain of parakeet hemoglobin highly similar grey lag goose and bar headed goose hemoglobin respectively. Thus it has been tempted us to study in to analyzing the sequence and structural comparison of this hemoglobin to find out the physiological capabilities of parakeet hemoglobin.

Objective: The structure determination studies of parakeet hemoglobin by X-ray diffraction. The sequence and structure are compared with goose, chicken and human Hb, emphasizing the role of amino acids in the subunit contacts that facilitate survival by low oxygen demand.

Methods: The Hb was purified and crystallized by hanging drop vapor diffusion method using poly ethylene glycol (PEG) 3350 and sodium phosphate buffer. X-ray diffracted data set was collected at 3Å resolution, the data was processed in Automar and molecular replacement, refinements, model building was carried out in CCP4i program package. The final refined model was deposited in protein data bank with accession id 2zfb.

Results: The tertiary structure of Parakeet Hb is compared with the met form of BHG Hb (1c40) and oxy form of GLG (1faw) and oxy form of human Hbs (1hho). Superimposing parakeet Hb α1β1 subunit with ‘R’ state human Hb shows an r.m.s.d of 0.98 Å and for BHG and GLG Hb, the r.m.s.d shows 0.72 and 0.61 Å. The replacement of α115Asp in parakeet Hb as against the α115Glu in human Hb results in the movement of GH corners. The amino acid proline at α50 present only in Parakeet Hb and Chicken HbD and not present in any other avian family which includes human Hb. The residue α78Thr located in EF corner loop region, which slightly diverge when superimposing with human and BHG Hb and also replacement of α113Asn present only in Parakeet Hb placed near the FG helix corner.

Conclusion: The present study describes the structure determination of parakeet hemoglobin and its structural features to understand its oxygen affinity characteristics. The crystals were obtained by buffered low-salt conditions, like those of chicken HbD, carbonmonoxy and cyanomet human Hb. The present study reveals several interesting and unique modifications in the finer aspects of the quaternary structure of parakeet Hb, which are involved in oxygen affinity characteristics and the α1β1 subunit contacts. Crystallization of parakeet Hb with allosteric effectors like Inositol pentaphosphate may bring further understanding of the influence of physiological and environmental factors on the quaternary structure.

Keywords: Parakeet, hemoglobin, oxygen affinity, X-ray diffraction, Psittacula krameri, avian.

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[1]
Imai, K. Allosteric Effects in Haemoglobin. Cambridge University Press, 1982.
[2]
Hsia, C.C. Respiratory function of hemoglobin. N. Engl. J. Med., 1998, 338(4), 239-247.
[http://dx.doi.org/10.1056/NEJM199801223380407] [PMID: 9435331]
[3]
Islam, A.; Beg, O.U.; Persson, B.; Zaidi, Z.H.; Jörnvall, H. Primary structure of the hemoglobin alpha-chain of rose-ringed parakeet (Psittacula krameri). J. Protein Chem., 1988, 7(5), 561-569.
[http://dx.doi.org/10.1007/BF01024874] [PMID: 3255379]
[4]
Islam, A.; Persson, B.; Zaidi, Z.H.; Jörnvall, H. Primary structure of the hemoglobin beta-chain of rose-ringed parakeet (Psittacula krameri). J. Protein Chem., 1989, 8(4), 481-486.
[http://dx.doi.org/10.1007/BF01026432] [PMID: 2803513]
[5]
Black, C.P.; Tenney, S.M. Oxygen transport during progressive hypoxia in high-altitude and sea-level waterfowl. Respir. Physiol., 1980, 39(2), 217-239.
[http://dx.doi.org/10.1016/0034-5687(80)90046-8] [PMID: 7375742]
[6]
Butler, P.J.; Jones, D.R. Physiology of diving of birds and mammals. Physiol. Rev., 1997, 77(3), 837-899.
[http://dx.doi.org/10.1152/physrev.1997.77.3.837] [PMID: 9234967]
[7]
Faraci, F.M. Adaptations to hypoxia in birds: how to fly high. Annu. Rev. Physiol., 1991, 53, 59-70.
[http://dx.doi.org/10.1146/annurev.ph.53.030191.000423] [PMID: 2042973]
[8]
Rollema, H.S.; Bauer, C. The interaction of inositol pentaphosphate with the hemoglobins of highland and lowland geese. J. Biol. Chem., 1979, 254(23), 12038-12043.
[PMID: 40989]
[9]
Oberthür, W.; Braunitzer, G.; Kalas, S. Hemoglobins, XLII: Studies on the hemoglobin of the greylag goose (Anser anser). The primary structures of the alpha- and beta-chains of the main component (author's transl). Hoppe Seylers Z Physiol. Chem., 1981, 362(8), 1101-1112.
[PMID: 7346378]
[10]
Liu, X.Z.; Li, S.L.; Jing, H.; Liang, Y.H.; Hua, Z.Q.; Lu, G.Y. Avian haemoglobins and structural basis of high affinity for oxygen: structure of bar-headed goose aquomet haemoglobin. Acta Crystallogr. D Biol. Crystallogr., 2001, 57(Pt 6), 775-783.
[http://dx.doi.org/10.1107/S0907444901004243] [PMID: 11375496]
[11]
Bartels, K.S.; Klein, C. The AUTOMAR Manual. v.1.4.3. MAR Research GmbH: Norderstedt, Germany, 2003.
[12]
Navaza, J. AMoRe: an automated package for molecular replacement. Acta Crystallogr. A, 1994, 50(2), 157-163.
[http://dx.doi.org/10.1107/S0108767393007597]
[13]
Collaborative Computational Project, Number 4. The CCP4 suite: programs for protein crystallography. Acta Crystallogr. D Biol. Crystallogr., 1994, 50(Pt 5), 760-763.
[http://dx.doi.org/10.1107/S0907444994003112] [PMID: 15299374]
[14]
Emsley, P.; Cowtan, K. Coot: model-building tools for molecular graphics. Acta Crystallogr D Biol Crystallogr, 2004, 60(Pt 12), 2126-2132.
[http://dx.doi.org/10.1107/S0907444904019158]
[15]
Laskowski, R.A.; Macarthur, M.W.; Moss, D.S.; Thornton, J.M. Procheck - A program to check the stereochemical quality of protein structures. J. Appl. Cryst., 1993, 26, 283-291.
[http://dx.doi.org/10.1107/S0021889892009944]
[16]
Ramachandran, G.N.; Sasisekharan, V. Conformation of polypeptides and proteins. Adv. Protein Chem., 1968, 23, 283-438.
[http://dx.doi.org/10.1016/S0065-3233(08)60402-7] [PMID: 4882249]
[17]
Zhang, J.; Hua, Z.; Tame, J.R.; Lu, G.; Zhang, R.; Gu, X. The crystal structure of a high oxygen affinity species of haemoglobin (bar-headed goose haemoglobin in the oxy form). J. Mol. Biol., 1996, 255(3), 484-493.
[http://dx.doi.org/10.1006/jmbi.1996.0040] [PMID: 8568892]
[18]
Shaanan, B. Structure of human oxyhaemoglobin at 2.1 A resolution. J. Mol. Biol., 1983, 171(1), 31-59.
[http://dx.doi.org/10.1016/S0022-2836(83)80313-1] [PMID: 6644819]
[19]
Liang, Y.; Hua, Z.; Liang, X.; Xu, Q.; Lu, G. The crystal structure of bar-headed goose hemoglobin in deoxy form: the allosteric mechanism of a hemoglobin species with high oxygen affinity. J. Mol. Biol., 2001, 313(1), 123-137.
[http://dx.doi.org/10.1006/jmbi.2001.5028] [PMID: 11601851]
[20]
Hiebl, I.; Braunitzer, G.; Schneeganss, D. The primary structures of the major and minor hemoglobin-components of adult Andean goose (Chloephaga melanoptera, Anatidae): the mutation Leuta-chains. Biol. Chem. Hoppe Seyler, 1987, 368(12), 1559-1569.
[http://dx.doi.org/10.1515/bchm3.1987.368.2.1559] [PMID: 3442599]
[21]
Knapp, J.E.; Oliveira, M.A.; Xie, Q.; Ernst, S.R.; Riggs, A.F.; Hackert, M.L. The structural and functional analysis of the hemoglobin D component from chicken. J. Biol. Chem., 1999, 274(10), 6411-6420.
[http://dx.doi.org/10.1074/jbc.274.10.6411] [PMID: 10037733]
[22]
Perutz, M.F. The Bohr effect and combination with organic phosphates. Nature, 1970, 228(5273), 734-739.
[http://dx.doi.org/10.1038/228734a0] [PMID: 16058681]
[23]
Safo, M.K.; Moure, C.M.; Burnett, J.C.; Joshi, G.S.; Abraham, D.J. High-resolution crystal structure of deoxy hemoglobin complexed with a potent allosteric effector. Protein Sci., 2001, 10(5), 951-957.
[http://dx.doi.org/10.1110/ps.50601] [PMID: 11316875]
[24]
Arnone, A. X-ray diffraction study of binding of 2,3-diphosphoglycerate to human deoxyhaemoglobin. Nature, 1972, 237(5351), 146-149.
[http://dx.doi.org/10.1038/237146a0] [PMID: 4555506]
[25]
Isaacks, R.; Harkness, D.; Sampsell, R.; Adler, J.; Roth, S.; Kim, C.; Goldman, P. Studies on avian erythrocyte metabolism. Inositol tetrakisphosphate: the major phosphate compound in the erythrocytes of the ostrich (Struthio camelus camelus). Eur. J. Biochem., 1977, 77(3), 567-574.
[http://dx.doi.org/10.1111/j.1432-1033.1977.tb11700.x] [PMID: 19258]
[26]
Vandecasserie, C.; Paul, C.; Schnek, A.G.; Léonis, J. Oxygen affinity of avian hemoglobins. Comp. Biochem. Physiol. A Comp. Physiol., 1973, 44(3), 711-718.
[http://dx.doi.org/10.1016/0300-9629(73)90136-9] [PMID: 4146620]
[27]
Kleinschmidt, T.; Sgouros, J.G. Hemoglobin sequences. Biol. Chem. Hoppe Seyler, 1987, 368(6), 579-615.
[PMID: 3304337]
[28]
Isaacks, R.E.; Harkness, D.R.; Adler, J.L.; Goldman, P.H. Studies on avian erythrocyte metabolism. Effect of organic phosphates on oxygen affinity of embryonic and adult-type hemoglobins of the chick embryo. Arch. Biochem. Biophys., 1976, 173(1), 114-120.
[http://dx.doi.org/10.1016/0003-9861(76)90240-X] [PMID: 4025]

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