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Blanco-Doval A, Sousa R, Barron LJR, Portmann R, Egger L, Aldai N. Assessment of in vitro digestibility and post-digestion peptide release of mare milk in relation to different management systems and lactation stages. J Dairy Sci 2024:S0022-0302(24)00902-0. [PMID: 38851572 DOI: 10.3168/jds.2024-24807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/08/2024] [Indexed: 06/10/2024]
Abstract
Mare milk has a unique protein composition that makes it a preferred option for adult and infant nutrition. Several functional properties have been attributed to this milk but with little evidence yet. In fact, knowledge on mare milk composition is still limited. In particular, studies addressing the performance of mare milk proteins during human gastrointestinal digestion are scarce, which limits the understanding of mare milk nutritional quality and functionality. For this reason, the present study describes the digestibility of mare milk proteins and the release of peptides as affected by management and lactation stage, factors known to affect milk composition. Mare milk samples from 3 different farms, and collected during 6 mo of lactation (n = 54), were subjected to a static in vitro gastrointestinal model to measure peptide release and protein digestibility. In the present study, a detailed description of protein and individual amino acid behavior during the digestion process was given. For the first time, digestion of the 2 equine β-lactoglobulin isoforms (I and II) was described individually. In addition, it was found that lactation stage and management system can significantly affect protein digestibility and peptide release during gastrointestinal digestion of mare milk. Presumably, differences in the composition of mare milk influence the protein structure and enzyme accessibility, which might have an impact on digestion behavior. Despite no specific bioactive peptides were identified, several precursors of previously described bioactive peptides were found. These findings could support the idea of mare milk as a food with added value.
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Affiliation(s)
- Ana Blanco-Doval
- Lactiker Research Group, Department of Pharmacy and Food Sciences, University of the Basque Country (UPV/EHU), Paseo de la Universidad 7, 01006 Vitoria-Gasteiz, Spain
| | - Raquel Sousa
- Agroscope, Schwarzenburgstrasse 161, 3003, Bern, Switzerland
| | - Luis Javier R Barron
- Lactiker Research Group, Department of Pharmacy and Food Sciences, University of the Basque Country (UPV/EHU), Paseo de la Universidad 7, 01006 Vitoria-Gasteiz, Spain
| | - Reto Portmann
- Agroscope, Schwarzenburgstrasse 161, 3003, Bern, Switzerland
| | - Lotti Egger
- Agroscope, Schwarzenburgstrasse 161, 3003, Bern, Switzerland
| | - Noelia Aldai
- Lactiker Research Group, Department of Pharmacy and Food Sciences, University of the Basque Country (UPV/EHU), Paseo de la Universidad 7, 01006 Vitoria-Gasteiz, Spain.
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D'Alessandro AG, Martemucci G, Jirillo E, De Leo V. Major whey proteins in donkey's milk: effect of season and lactation stage. Implications for potential dietary interventions in human diseases. Immunopharmacol Immunotoxicol 2010; 33:259-65. [PMID: 20624015 DOI: 10.3109/08923973.2010.499365] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
According to current literature, donkey's milk has been suggested as a hypoallergenic substitute in children affected by cow's milk protein allergy as well as a promising nutraceutical for aged people. However, the biologically active components of donkey's milk have not yet completely elucidated. In this framework this study is aimed at measuring α-lactalbumin (α-LA), β-lactoglobulin (β-LG), and lysozyme (LYS), the principal whey proteins in donkey's milk, in relation to lactation stage and production season. Analysis were performed by reversed-phase high-performance liquid chromatography. α-LA, β-LG, and LYS resulted to be affected by lactation stage (P < 0.01) and production season (P < 0.01). Overall, the protein content was higher (0.01 > P < 0.05) during the first four lactation's months and decreased until the month 8. The β-LG was the major protein (1.75 mg mL(-1) as mean; peak 2.24 ± 0.09 mg mL(-1)), while the α-LA had a mean concentration of 1.32 mg mL(-1) and peaked at month 1 (1.57 ± 0.09 mg mL(-1)) and LYS (0.66 mg mL(-1) as mean) showed the highest value equal to 0.76 ± 0.03 mg mL(-1). The highest (P < 0.01) concentration of all proteins was recorded at spring (α-LA: 1.69 mL(-1); β-LG: 2.07 mL(-1); LYS: 0.76 mL(-1)).
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Barello C, Garoffo LP, Montorfano G, Zava S, Berra B, Conti A, Giuffrida MG. Analysis of major proteins and fat fractions associated with mare's milk fat globules. Mol Nutr Food Res 2008; 52:1448-56. [DOI: 10.1002/mnfr.200700311] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Cunsolo V, Saletti R, Muccilli V, Foti S. Characterization of the protein profile of donkey's milk whey fraction. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:1162-74. [PMID: 17605147 DOI: 10.1002/jms.1247] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Characterization of the protein profile of the whey fraction from a milk sample taken from an individual donkey belonging to the 'Ragusana' species of the East of Sicily is reported. Direct RP-HPLC/electrospray ionization (ESI)-MS analysis of the whey fraction allowed the detection of some unknown components, together with the identification of already known whey proteins. Matrix-assisted laser desorption/ionization (MALDI)-TOF/MS and RP-HPLC/ESI-MS/MS analysis of the enzymatic digests of the unknown components resulted the identification and characterization of (1) two beta-casein fragments; (2) the sequence of donkey's serum albumin; and (3) the oxidized methionine forms of lysozyme B and alpha-lactoalbumin. One of the two beta-casein fragments corresponds to the sequence Val(176)-Arg(189) of the horse's beta-casein. The second one corresponds the C-terminal sequence Tyr(199)-Val(226) of the horse's beta-casein, with four amino acid substitutions (Q --> R(203), L/I --> P(206), F --> L(210) and P --> A(219)). Both fragments, reasonably arising by endogenous proteases cleavage of the donkey's beta-casein, could be potential biologically active peptides. Direct mass spectrometric sequence characterization of the detected donkey's serum albumin reveals the presence of the amino acid substitution Val --> Ile at position 497 with respect to the cDNA deduced sequence. The oxidized forms of lysozyme B and alpha-lactoalbumin are selectively oxidized at methionine 79 and methionine 90, respectively.
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Affiliation(s)
- Vincenzo Cunsolo
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Viale A Doria, 6, I-95125, Catania, Italy
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Cunsolo V, Costa A, Saletti R, Muccilli V, Foti S. Detection and sequence determination of a new variant beta-lactoglobulin II from donkey. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:1438-46. [PMID: 17377935 DOI: 10.1002/rcm.2978] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The sequence determination of a new variant of beta-LG II, detected as a minor component by reversed-phase high-performance liquid chromatography/electrospray ionization mass spectrometry (RP-HPLC/ESI-MS) analysis of the whey fraction from a milk sample taken from an individual donkey belonging to the 'Ragusana' species of eastern Sicily, is reported. Direct RP-HPLC/ESI-MS analysis of the whey fraction from this milk sample allowed the identification of a new variant of beta-LG II, based on the determination of the M(r) of the intact protein. The new protein, with an experimentally determined M(r) of 18311 Da, was detected as a minor component in the whey fraction investigated. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF)MS and RP-HPLC/ESI-MS/MS analyses of the tryptic digest of the new protein demonstrate that it presents two amino acid substitutions with respect to the sequence of beta-LG II A, namely a substitution Pro-->Cys at position 110, and a substitution Asp-->Gly at position 162. The disulfide bonds between the four cysteines, not directly determined in donkey's and horse's beta-LG II, were shown to occur between Cys(106)-Cys(120) and Cys(66)-Cys(161), as in other mammalian beta-LGs. The new beta-LG II variant from donkey was named D.
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Affiliation(s)
- Vincenzo Cunsolo
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Viale A. Doria 6, I-95125 Catania, Italy
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Girardet JM, N’negue MA, Egito A, Campagna S, Lagrange A, Gaillard JL. Multiple forms of equine α-lactalbumin: evidence for N-glycosylated and deamidated forms. Int Dairy J 2004. [DOI: 10.1016/j.idairyj.2003.08.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Businco L, Giampietro PG, Lucenti P, Lucaroni F, Pini C, Di Felice G, Iacovacci P, Curadi C, Orlandi M. Allergenicity of mare's milk in children with cow's milk allergy. J Allergy Clin Immunol 2000; 105:1031-4. [PMID: 10808187 DOI: 10.1067/mai.2000.106377] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Cow's milk allergy is a common disease of infancy and early childhood. If the baby is not breast-fed, a substitute for cow's milk formula is necessary. OBJECTIVE The aim of this study was to investigate, in vitro and in vivo, the allergenicity of mare's milk in a population of selected children with severe IgE-mediated cow's milk allergy. METHODS Twenty-five children (17 male and 8 female) aged 19 to 72 months (median age 34 months) with IgE-mediated cow's milk allergy were selected for this study. All the children underwent skin prick tests with cow's milk and mare's milk and double-blind placebo-controlled oral food challenge (DBPCOFC) with fresh cow's milk, fresh mare's milk, and, as placebo, a soy formula (Isomil, Abbott, Campoverde, Italy). We performed immunoblotting of cow's and mare's milk developed with IgE from allergic children. RESULTS All the children showed strong positive skin test responses to cow's milk (4+); 2 children had positive skin test responses to mare's milk (2+). All children had positive DBPCOFCs to cow's milk; one child had a positive DBPCOFC to mare's milk. No children reacted to the placebo (Isomil). In the cow's milk, some proteins are able to strongly react with human IgE; when the sera are tested with mare's milk, the bands corresponding to the same proteins are recognized by a lower percentage of sera. CONCLUSION These data suggest that mare's milk can be regarded as a good substitute of cow's milk in most children with severe IgE-mediated cow's milk allergy. It would be prudent, however, to confirm its tolerability by a supervised titrated oral challenge test.
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Affiliation(s)
- L Businco
- Division of Allergy and Clinical Immunology, Department of Pediatrics, University La Sapienza, Rome, Italy
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Herrouin M, Mollé D, Fauquant J, Ballestra F, Maubois JL, Léonil J. New genetic variants identified in donkey's milk whey proteins. JOURNAL OF PROTEIN CHEMISTRY 2000; 19:105-15. [PMID: 10945434 DOI: 10.1023/a:1007078415595] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Novel genetic variants for donkey milk lysozyme and beta-lactoglobulins I and II have been identified by the combined use of peptide mass mapping and sequencing by tandem mass spectrometry in association with database searching. The novel donkey lysozyme variant designated as lysozyme B (Mr 14,631 Da) differed in three amino acid exchanges, N49 --> D, Y52 --> S, and S61 --> N, from the previously published sequence. Three novel genetic variants for donkey beta-lactoglobulins were identified. One of them is a type beta-lactoglobulin I with three amino acid exchanges at E36 --> S, S97 --> T, and V150 --> I (beta-lactoglobulin I B, Mr 18,510 Da). The two others are type beta-lactoglobulins II with two amino acid exchanges at C110 --> P and M118--> T (beta-lactoglobulin II B, Mr 18,227 Da) and with three amino acid exchanges at D96 --> E, C110 --> P, and M118 -->T (beta-lactoglobulin II C, Mr 18,241 Da). All these primary structures are closely related to those of homologous proteins in horse milk (percent identity >96%).
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Affiliation(s)
- M Herrouin
- EURL François Ballestra, SAINT-RAPHAEL, France
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12
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Haezebrouck P, Noppe W, Van Dael H, Hanssens I. Hydrophobic interaction of lysozyme and alpha-lactalbumin from equine milk whey. BIOCHIMICA ET BIOPHYSICA ACTA 1992; 1122:305-10. [PMID: 1504092 DOI: 10.1016/0167-4838(92)90409-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
From fluorescence measurements on mixtures of bis-ANS and equine lysozyme and from Ca(2+)-dependent hydrophobic interaction chromatography of equine lysozyme, it is demonstrated that Ca2+ binding induces a conformational change upon which hydrophobic regions in the protein become less accessible. Bis-ANS fluorescence titrations in the absence of Ca2+ and in 2 mM Ca2+ are also performed with equine alpha-lactalbumin variants B and C. These variants differ by an amino-acid exchange Asp----Ile at residue 95. The fluorescence titration curves indicate that the accessibility of the probe to the Ca2+ conformers is clearly influenced by the mutation. The Ca(2+)-dependent exclusion of a hydrophobic domain is used in a new and simplified method for preparing lysozyme and alpha-lactalbumins simultaneously from equine milk whey.
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Affiliation(s)
- P Haezebrouck
- Interdisciplinary Research Center, K.U.L. Campus Kortrijk, Belgium
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Vilotte JL, Soulier S, Mercier JC. Sequence of the murine alpha-lactalbumin-encoding cDNA: interspecies comparison of the coding frame and deduced pre-protein. Gene 1992; 112:251-5. [PMID: 1555774 DOI: 10.1016/0378-1119(92)90385-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The structure of the mouse alpha-lactalbumin-encoding mRNA was deduced from sequence analysis of eight cDNA clones. The almost full-length mRNA of 732 nucleotides [poly(A) tail excluded] and the deduced pre-protein share 85% and 86% homology with their rat counterpart, respectively. Interspecies comparison of the pre-protein showed the occurrence of an extra amino acid (aa) in the signal peptide and of two mutations affecting two reported invariant aa residues at positions 44 and 107, which weakens the assumption that both aa residues might play a significant structural and/or functional role.
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Affiliation(s)
- J L Vilotte
- Laboratoire de Génétique Biochimique, INRA-CRJ, Jouy-en-Josas, France
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Abstract
A cDNA clone encoding porcine alpha-lactalbumin (alpha LA) was isolated and sequenced. The longest clone was 688 nucleotides (nt) long and encoded a preprotein of 141 amino acids (aa) including a leader peptide of 19 aa. The porcine cDNA exhibited a nt similarity of between 72.2%-83.5% to other alpha LA cDNAs and an aa similarity of between 50.8%-85.2% with other alpha LA aa sequences. The derived aa sequence varied at three positions from a previously reported sequence for porcine alpha LA obtained by direct aa sequencing.
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Affiliation(s)
- N A Das Gupta
- Division of Surgical Oncology, University of Illinois, Chicago 60612
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Tsuge H, Koseki K, Miyano M, Shimazaki K, Chuman T, Matsumoto T, Noma M, Nitta K, Sugai S. A structural study of calcium-binding equine lysozyme by two-dimensional 1H-NMR. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1078:77-84. [PMID: 1646637 DOI: 10.1016/0167-4838(91)90095-h] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Since 1H-NMR spectra of the calcium bound form (holo) and the calcium free form (apo) of equine lysozyme have an overall similarity, the folded structure of apo equine lysozyme seems to be similar to the holo structure at 25 degrees C and pH 7.0, even at low ionic strengths except for subtle conformational change. However, calcium titration experiments showed that a number of resonances change by a slow exchange process. The changes saturated at one calcium ion per one lysozyme molecule, and no more change was observed by further addition of calcium ions. This shows that just one calcium ion binds to equine lysozyme. To make assignments for these changed proton resonances, two-dimensional 1H-NMR studies, correlated spectroscopy (COSY), two-dimensional homonuclear Hartmann-Hahn spectroscopy (HOHAHA) and nuclear Overhauser effect spectroscopy (NOESY) were carried out. A structural model of equine lysozyme based on the crystal structure of human lysozyme was estimated and used to assign some resonances in the aromatic and beta-sheet regions. It was possible to use some proton signals as a probe to determine the specific conformational change induced by calcium ions. The calcium binding constant KCa was estimated from calcium titration experiments in which changes in the proton signal were monitored. The log KCa value was found to be on the order of 6-7, which is in agreement with the calcium binding constant determined by fluorescence probes. This means that the protons are affected by specific calcium binding.
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Affiliation(s)
- H Tsuge
- Life Science Research Laboratory, Japan Tabacco, Inc., Kanagawa
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McKenzie HA, White FH. Lysozyme and alpha-lactalbumin: structure, function, and interrelationships. ADVANCES IN PROTEIN CHEMISTRY 1991; 41:173-315. [PMID: 2069076 DOI: 10.1016/s0065-3233(08)60198-9] [Citation(s) in RCA: 177] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- H A McKenzie
- Department of Chemistry, University College, University of New South Wales, Australian Defence Force Academy, Canberra, ACT, Australia
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Godovac-Zimmermann J, Conti A, Napolitano L. The complete primary structure of alpha-lactalbumin isolated from pig (Sus scrofa) milk. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1990; 371:649-53. [PMID: 2222864 DOI: 10.1515/bchm3.1990.371.2.649] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The complete amino-acid sequence of pig alpha-lactalbumin has been determined. It was obtained by microsequencing of the native protein and the peptides derived after tryptic or cyanogen bromide cleavage. The tryptic peptides were separated by a rapid microbore HPLC method. Pig alpha-lactalbumin is 122 amino acids long and differs from the bovine homologue by 26 exchanged residues. Of the two prolines present in bovine alpha-lactalbumin, one has been deleted in the pig structure. All previously sequenced alpha-lactalbumins have shown glutamic acid at position 49, which is known to be the active site in the homologous lysozyme c structure. This residue is replaced by phenylalanine in pig alpha-lactalbumin indicating that the pig protein is the first alpha-lactalbumin with complete loss of all lysozyme functional residues.
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Affiliation(s)
- J Godovac-Zimmermann
- John Curtin School of Medical Research, Australian National University, Canberra
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Harushima Y, Sugai S. Hydrogen exchange of the tryptophan residues in bovine, goat, guinea pig, and human alpha-lactalbumin. Biochemistry 1989; 28:8568-76. [PMID: 2605208 DOI: 10.1021/bi00447a045] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Hydrogen exchange of the individual tryptophan residues of bovine, goat, guinea pig, and human alpha-lactalbumin has been studied by both ultraviolet and NMR spectra. The assignment of the slowly exchanging imino proton resonances to the tryptophan residues (Trp26 and Trp60) was obtained by comparison of the nuclear Overhauser effect difference spectra of bovine, guinea pig, and human alpha-lactalbumin. Taking account of the thermal unfolding of each alpha-lactalbumin, the hydrogen exchange rates of the individual tryptophan residues are analyzed. The temperature dependence of the exchange rates classified their exchange mechanisms into two exchange processes: the "low activation energy process" and the "high activation energy process" which is associated directly with the global thermal unfolding of the protein. Trp26 of alpha-lactalbumin exchanges through the high activation energy process. The exchange behavior of Trp26 of guinea pig alpha-lactalbumin suggests a difference of the globally unfolded state of the protein from the other species. The exchange mechanism of Trp60 of human alpha-lactalbumin is the low activation energy process in contrast with those of the bovine and goat proteins, although their global thermodynamic properties are similar to each other. Trp104 and Trp118 of alpha-lactalbumin exchange through the low activation energy process, and the reaction rates are affected by the local structural differences around the tryptophan residues among these proteins. The results presented in this paper indicate that the hydrogen exchange rate through the low activation energy process provides the information only about the local nature of a protein while that through the high activation energy process provides the information about the global nature of a protein.
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Affiliation(s)
- Y Harushima
- Department of Polymer Science, Faculty of Science, Hokkaido University, Japan
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Abstract
From the analysis of phylogenetic trees constructed from the amino acid sequences and metal-binding properties of various lysozymes c and alpha-lactalbumins, it was found that before the divergence of the lineages of birds and mammals, calcium-binding lysozyme diverged from non-calcium-binding lysozyme. alpha-Lactalbumin evolved from the calcium-binding lysozyme along the mammalian lineage after the divergence of birds and mammals. Rapid evolution took place, not in the process of acquisition of the activity of alpha-lactalbumin, but after the loss of lysozyme activity, due to the change in the distribution of selective pressure on each amino acid site. A general process for the change in function of a protein during evolution is suggested to be as follows: after duplication of the gene, one of their protein products acquires a new function, besides that already present; the old function is eventually lost.
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Affiliation(s)
- K Nitta
- Department of Polymer Science, Faculty of Science, Hokkaido University, Japan
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Godovac-Zimmermann J, Conti A, James L, Napolitano L. Microanalysis of the amino-acid sequence of monomeric beta-lactoglobulin I from donkey (Equus asinus) milk. The primary structure and its homology with a superfamily of hydrophobic molecule transporters. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1988; 369:171-9. [PMID: 3370127 DOI: 10.1515/bchm3.1988.369.1.171] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The complete primary structure of donkey beta-lactoglobulin I was determined by pulsed-liquid phase microsequencing of tryptic peptides. The protein has been isolated in monomeric form and it corresponds to monomeric beta-lactoglobulin of type I. With the inclusion of donkey beta-lactoglobulin I there are 13% common residues amongst the members of the beta-lactoglobulin family. Donkey beta-lactoglobulin I is homologous to the retinol-binding protein, bilin-binding protein and five other proteins belonging to the new superfamily of hydrophobic molecule transporters. A rapid method for peptide isolation and the strategy for microsequencing of this protein have been described.
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Affiliation(s)
- J Godovac-Zimmermann
- Department of Biochemistry, John Curtin School of Medical Research, Australian National University, Canberra
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Abstract
It was found that equine lysozyme binds one Ca2+. It was eluted with equimolar Ca2+ from a Bio-Gel P-4 column. Human lysozyme did not behave similarly. Equine lysozyme is concluded to be a calcium metallo-protein like alpha-lactalbumin, which is a homologue of hen egg white lysozyme.
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Affiliation(s)
- K Nitta
- Department of Polymer Science, Faculty of Science, Hokkaido University, Japan
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