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Pandolfi L, Frangipane V, D'Amato M, Bozzini S, Viglio S, Iadarola P, De Amici M, Lettieri S, Morosini M, Meloni F. NETosis in Broncho-Alveolar Lavage-Fluid (BAL-f) from Bronchiolitis Obliterans Syndrome (BOS) Patients. J Heart Lung Transplant 2021. [DOI: 10.1016/j.healun.2021.01.859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Fumagalli M, Gerace D, Faè M, Iadarola P, Leelavathi S, Reddy VS, Cella R. Molecular, biochemical, and proteomic analyses of transplastomic tobacco plants expressing an endoglucanase support chloroplast-based molecular farming for industrial scale production of enzymes. Appl Microbiol Biotechnol 2019; 103:9479-9491. [PMID: 31701198 DOI: 10.1007/s00253-019-10186-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 10/01/2019] [Accepted: 10/07/2019] [Indexed: 01/02/2023]
Abstract
The successful production of recombinant enzymes by tobacco transplastomic plants must maintain compatibility of the heterologous enzyme with chloroplast metabolism and its long-time enzyme stability. Based on previous reports, it has been taken for granted that following biolistic-transformation, homoplasticity could be obtained from the initially heteroplastic state following successive rounds of selection in the presence of the selection agent. However, several studies indicated that this procedure does not always ensure the complete elimination of unmodified wild-type plastomes. The present study demonstrates that CelK1 transplastomic plants, which were photosyntetically as active as untransformed ones, remain heteroplastomic even after repeated selection steps and that this state does not impair the relatively high-level production of the recombinant enzyme. In fact, even in the heteroplastomic state, the recombinant protein represented about 6% of the total soluble proteins (TSP). Moreover, our data also show that, while the recombinant endoglucanase undergoes phosphorylation, this post-translation modification does not have any significant impact on the enzymatic activity. Biomass storage might be required whenever the enzyme extraction process could not be performed immediately following the harvest of tobacco mature plants. In this respect, we have observed that enzyme activity in the detached leaves stored at 4 °C is maintained up to 20 weeks without significant loss of activity. These findings may have major implications in the future of chloroplast genetic engineering-based molecular farming to produce industrial enzymes in transplastomic plants.
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Affiliation(s)
- M Fumagalli
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - D Gerace
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - M Faè
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - P Iadarola
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - S Leelavathi
- Plant Transformation Group, International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - V S Reddy
- Plant Transformation Group, International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Rino Cella
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy.
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Frankenberger M, Heimbeck I, Möller W, Mamidi S, Kassner G, Pukelsheim K, Wjst M, Neiswirth M, Kroneberg P, Lomas D, Halsall D, Iadarola P, Fertl A, Häussinger K, Ziegler-Heitbrock L. Inhaled all-trans retinoic acid in an individual with severe emphysema. Eur Respir J 2010; 34:1487-9. [PMID: 19948915 DOI: 10.1183/09031936.00105309] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Lupi A, Perugini P, Genta I, Modena T, Conti B, Casado B, Cetta G, Pavanetto F, Iadarola P. Biodegradable microspheres for prolidase delivery to human cultured fibroblasts. J Pharm Pharmacol 2010; 56:597-603. [PMID: 15142336 DOI: 10.1211/0022357023349] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Prolidase deficiency (PD) is a rare autosomal recessive disorder caused by inadequate levels of the cytosolic exopeptidase prolidase (E.C. 3.4.13.9), for which there is not, as yet, a resolutive cure. We have investigated whether biodegradable microspheres loaded with prolidase could release active enzyme inside cells, to consider this system as a possible therapeutic approach for prolidase deficiency. Poly(lactide-co-glycolide) microspheres were prepared, modifying the classical double emulsion solvent evaporation method to mitigate the burst effect of the enzyme from the microspheres. Ex-vivo experiments were performed, by incubating microencapsulated prolidase with cultured fibroblasts from PD patients and from controls, to determine the amount of active enzyme delivered to the cells. The microparticulate drug delivery system described carried small amounts of active prolidase inside fibroblasts, ensuring a response to the intracellular accumulation of X-Pro dipeptides, the mechanism that is supposed to be responsible for the development of clinical manifestations of this disorder in man. A positive result of the presence of active enzyme inside cells was an improvement in fibroblast shape.
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Affiliation(s)
- A Lupi
- Department of Biochemistry "A. Castellani", University of Pavia, V.le Taramelli 3/B, 27100 Pavia, Italy
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Casado B, Pannell L, Iadarola P, Baraniuk J. IDENTIFICATION OF LIPOCALIN FAMILY PROTEINS IN NASAL SECRETIONS. Exp Lung Res 2009. [DOI: 10.1080/01902140390194250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Luisetti M, Ma S, Iadarola P, Stone PJ, Viglio S, Casado B, Lin YY, Snider GL, Turino GM. Desmosine as a biomarker of elastin degradation in COPD: current status and future directions. Eur Respir J 2009; 32:1146-57. [PMID: 18978133 DOI: 10.1183/09031936.00174807] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Desmosine (DES) and isodesmosine (IDES) are two unusual, tetrafunctional, pyridinium ring-containing amino acids involved in elastin cross-linking. Being amino acids unique to mature, cross-linked elastin, they are useful for discriminating peptides derived from elastin breakdown from precursor elastin peptides. According to these features, DES and IDES have been extensively discussed as potentially attractive indicators of elevated lung elastic fibre turnover and markers of the effectiveness of agents with the potential to reduce elastin breakdown. In the present manuscript, immunology-based and separation methods for the evaluation of DES and IDES are discussed, along with studies reporting increased levels of urine excretion in chronic obstructive pulmonary disease (COPD) patients with and without alpha(1)-antitrypsin deficiency. The results of the application of DES and IDES as surrogate end-points in early clinical trials in COPD are also reported. Finally, recent advances in detection techniques, including liquid chromatography tandem mass spectrometry and high-performance capillary electrophoresis with laser-induced fluorescence, are discussed. These techniques allow detection of DES and IDES at very low concentration in body fluids other than urine, such as plasma or sputum, and will help the understanding of whether DES and IDES are potentially useful in monitoring therapeutic intervention in COPD.
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Affiliation(s)
- M Luisetti
- Laboratory of Biochemistry and Genetics, Institute of Respiratory Disease, IRCCS San Matteo Hospital Foundation, Pavia, Italy.
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Boschetto P, Quintavalle S, Zeni E, Leprotti S, Potena A, Ballerin L, Papi A, Palladini G, Luisetti M, Annovazzi L, Iadarola P, De Rosa E, Fabbri LM, Mapp CE. Association between markers of emphysema and more severe chronic obstructive pulmonary disease. Thorax 2006; 61:1037-42. [PMID: 16769715 PMCID: PMC2117071 DOI: 10.1136/thx.2006.058321] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND The predominant emphysema phenotype is associated with more severe airflow limitation in patients with chronic obstructive pulmonary disease (COPD). A study was undertaken to investigate whether COPD patients, with or without emphysema quantitatively confirmed by high resolution computed tomography (HRCT), have different COPD severity as assessed by the BODE index (body mass index, airflow obstruction, dyspnoea, exercise performance) and inspiratory capacity to total lung capacity ratio (IC/TLC), and by different biological markers of lung parenchymal destruction. METHODS Twenty six outpatients with COPD and eight healthy non-smokers were examined. Each subject underwent HRCT scanning, pulmonary function tests, cell counts, and measurements of neutrophil elastase, matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 in induced sputum, as well as measurement of desmosine, a marker of elastin degradation in urine, plasma and sputum. RESULTS Patients with HRCT confirmed emphysema had a higher BODE index and lower IC/TLC ratio than subjects without HRCT confirmed emphysema and controls. Forced expiratory volume in 1 second (FEV(1)), FEV(1)/forced vital capacity ratio, and carbon monoxide transfer coefficient were lower, whereas the number of eosinophils, MMP-9, and the MMP-9/TIMP-1 ratio in sputum were higher in patients with emphysema. In COPD patients the number of sputum eosinophils was the biological variable that correlated positively with the HRCT score of emphysema (p = 0.04). CONCLUSIONS These results suggest that COPD associated with HRCT confirmed emphysema is characterised by more severe lung function impairment, more intense airway inflammation and, possibly, more serious systemic dysfunction than COPD not associated with HRCT confirmed emphysema.
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Affiliation(s)
- P Boschetto
- Department of Experimental and Clinical Medicine, University of Ferrara, Italy.
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Casado B, Pannell L, Iadarola P, Baraniuk J. Proteomic analysis of normal human nasal mucus. J Allergy Clin Immunol 2005. [DOI: 10.1016/j.jaci.2004.12.246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Annovazzi L, Viglio S, Gheduzzi D, Pasquali-Ronchetti I, Zanone C, Cetta G, Iadarola P. High levels of desmosines in urine and plasma of patients with pseudoxanthoma elasticum. Eur J Clin Invest 2004; 34:156-64. [PMID: 14764080 DOI: 10.1111/j.1365-2362.2004.01306.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Pseudoxanthoma elasticum (PXE), a rare heritable disorder caused by mutations of the ABCC6 gene, is characterized by fragmentation and mineralization of elastic fibres. We determined the extent of degradation of elastin by measuring and comparing the amount of desmosines in plasma and urine of PXE patients, healthy carriers and normal subjects. METHODS Using capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) we measured the amount of desmosines in the urine of 46 individuals (14 PXE patients, 17 healthy carriers and 15 controls) and in the plasma of 56 subjects (18 PXE patients, 23 healthy carriers and 15 controls). Pseudoxanthoma elasticum patients and carriers were identified by clinical, structural and molecular biology analyses. RESULTS The urinary excretion of desmosines was two-fold higher in PXE patients than in controls (P < 0.01); the values for healthy carriers were intermediate between those of PXE patients and controls. A very similar trend between patients and their relatives was observed for plasma desmosines. There was a significant correlation between the amount of the desmosines in plasma and urine. Moreover, a positive correlation was observed between urinary desmosine content and age of the patients as well as between urinary desmosine content and severity of clinical manifestations. CONCLUSIONS Both the urinary and plasma desmosine concentrations indicate that elastin degradation is higher in PXE patients and, to a lesser extent, in healthy carriers than in normal subjects. Data seem to indicate that the amount of elastin breakdown products correlates with the age of patients as well as with the severity of the disease.
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Affiliation(s)
- L Annovazzi
- Università di Pavia, Pavia, and Università di Modena e Reggio Emilia, Modena, Italy
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Casado B, Pannell L, Iadarola P, Baraniuk J. IDENTIFICATION OF LIPOCALIN FAMILY PROTEINS IN NASAL SECRETIONS. Exp Lung Res 2003. [DOI: 10.1080/01902140303765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Lupi A, Casado B, Soli M, Bertazzoni M, Annovazzi L, Viglio S, Cetta G, Iadarola P. Therapeutic apheresis exchange in two patients with prolidase deficiency. Br J Dermatol 2002; 147:1237-40. [PMID: 12452876 DOI: 10.1046/j.1365-2133.2002.04998.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Prolidase deficiency is a rare genetic disorder for which a cure has not yet been found. OBJECTIVES To assess the effectiveness of apheresis exchange as a new therapeutic approach. METHODS Apheresis exchanges were repeated monthly for four consecutive months, in parallel, on two patients, replacing prolidase-deficient red blood cells with normal filtered cells. Prolidase activity and urinary dipeptides were determined at regular intervals. RESULTS The constant presence of active prolidase inside cells allowed a continuous, although partial, degradation of imidodipeptides, with a concomitant improvement of skin ulceration. CONCLUSIONS Apheresis exchange could be a reasonable way of obtaining a clinical improvement in these patients.
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Affiliation(s)
- A Lupi
- Department of Biochemistry A.Castellani, University of Pavia, Via Taramelli 3/B, I-27100 Pavia, Italy
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Genta I, Perugini P, Pavanetto F, Maculotti K, Modena T, Casado B, Lupi A, Iadarola P, Conti B. Enzyme loaded biodegradable microspheres in vitro ex vivo evaluation. J Control Release 2001; 77:287-95. [PMID: 11733096 DOI: 10.1016/s0168-3659(01)00511-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Prolidase is a naturally occurring enzyme involved in the final stage of protein catabolism. Deficient enzyme activity causes prolidase deficiency (PD), a rare autosomal recessive inherited disorder whose main manifestations are chronic, intractable ulcerations of the skin, particularly of lower limbs. Although several attempts have been made towards the treatment of this pathology, a cure for this disease has yet to be found. The purpose of this work is to evaluate the possibility of enzyme replacement therapy through prolidase microencapsulation in biodegradable microspheres. The poly(D,L-lactide-co-glycolide) (PLGA) prolidase loaded microparticulate systems have been prepared utilizing the w-o-w double emulsion solvent evaporation method. They have been characterized "in vitro" by morphological analysis, total protein content and an in vitro dissolution test of active protein. "Ex vivo" evaluation of prolidase activity from the microspheres has been performed on cellular extracts of cultured skin fibroblasts from healthy subjects (controls) and from patients affected by PD. The results reported in this work on prolidase from pig kidney (available on the market) demonstrate the positive role of microencapsulation as a process of enzymatic activity stabilization inside PLGA microspheres achieving both in vitro and ex vivo active enzyme release. This formulation can be proposed as a parenteral depot drug delivery system.
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Affiliation(s)
- I Genta
- Department of Pharmaceutical Chemistry, A. Castellani, University of Pavia, V. le Taramelli 12, 27100, Pavia, Italy
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Gorrini M, Lupi A, Viglio S, Pamparana F, Cetta G, Iadarola P, Powers JC, Luisetti M. Inhibition of human neutrophil elastase by erythromycin and flurythromycin, two macrolide antibiotics. Am J Respir Cell Mol Biol 2001; 25:492-9. [PMID: 11694455 DOI: 10.1165/ajrcmb.25.4.4552] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Fourteen-member-ring macrolides are antibiotics with a variety of anti-inflammatory activities, and have repeatedly been reported to reduce mucus hypersecretion in conditions such as cystic fibrosis and bronchiectasis. Their structure is characterized by a macrocyclic lactone ring. Because human neutrophil elastase (HNE) plays a crucial role in the vicious circle leading to mucus hypersecretion, and lactones are known to be elastase inhibitors, we hypothesized that macrolides might directly inhibit elastase. To investigate this hypothesis we designed a series of spectrophotometric experiments using a chromogenic substrate with two macrolides, erythromycin (Er) and flurythromycin (FE). We determined the 1st order rate constant (k(obs)) by inhibition and competitive substrate assays, the latter allowing us to calculate the substrate binding constant or inhibition constant and the acylation rate constant (k(a)). A proflavine displacement assay was used to determine the deacylation rate constant (k(d)). Both Er and FE are good HNE inhibitors, showing a high k(a) and a low k(d). Because the number of turnovers per inactivation of Er was congruent with 20-fold higher than that of FE, we supposed that the lower reactivation of HNE-FE was due to the formation of a more stable inactivated enzyme. This hypothesis was confirmed by the hydrazine reactivation of the acyl enzyme. For Er we identified a k(d) only, whereas for FE, in addition to the k(d), an alkylation constant (k(2)) was calculated, correlated to a fully inactivated enzyme. From our kinetics data, we therefore conclude that Er acts as an alternate substrate HNE inhibitor, whereas FE acts as an inactivator.
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Affiliation(s)
- M Gorrini
- Clinica di Malattie dell'Apparato Respiratorio, Laboratorio di Biochimica e Genetica, IRCCS Policlinico San Matteo, Via Taramelli 5, 27100 Pavia, Italy
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Viglio S, Marchi E, Wisniewski K, Casado B, Cetta G, Iadarola P. Diagnosis of late-infantile neuronal ceroid lipofuscinosis: a new sensitive method to assay lysosomal pepstatin-insensitive proteinase activity in human and animal specimens by capillary electrophoresis. Electrophoresis 2001; 22:2343-50. [PMID: 11504071 DOI: 10.1002/1522-2683(20017)22:11<2343::aid-elps2343>3.0.co;2-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Batten disease, or human late-infantile neuronal ceroid lipofuscinosis (LINCL) is a familiar progressive degenerative disease affecting children, caused by a deficiency of a lysosomal proteinase (tripeptidyl peptidase I, TPP-I) and characterized by the accumulation of autofluorescent storage bodies in the brain and other tissues of the body. Current methodology used to diagnose this disease needs to be improved in order to have less invasive techniques with higher resolution and shorter assay time. In this report, we discuss the potential merits of micellar electrokinetic chromatography as an excellent tool that requires minute samples but offers high resolution and a short running time for monitoring TPP-I activity in human and animal specimens.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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Abstract
A capillary isoelectric focusing (CIEF) method using bare fused-silica capillaries filled with polyethylene oxide (PEO) and carrier ampholyte solutions in the pH 3.5-5.0 range has been developed for the identification of alpha1-antitrypsin (alpha1AT) phenotypes in human serum. This novel procedure was routinely applied to the study of serum samples of five controls whose alpha1AT phenotype was previously identified and of twelve subjects whose alpha1AT phenotype was unknown. The results obtained allowed us to confirm or identify the alpha1AT phenotype in all sera tested. This procedure seems particularly suitable for identification of alpha1AT variants associated with diseases of clinical relevance.
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Affiliation(s)
- A Lupi
- Dipartimento di Biochemica A. Castellani, Università di Pavia, Italy
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Lupi A, Viglio S, Luisetti M, Zanaboni G, Cetta G, Iadarola P. Separation of closely related peptide substrates of human proteinases by micellar electrokinetic chromatography with anionic and nonionic surfactants. Electrophoresis 2000; 21:1985-91. [PMID: 10879957 DOI: 10.1002/1522-2683(20000601)21:10<1985::aid-elps1985>3.0.co;2-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In order to use micellar electrokinetic chromatography to determine the proteolytic activity of different proteinases simultaneously present in physiological fluids, the technique must be able to separate mixtures of substrates with closely related structures. In an attempt to determine the best electrophoretic conditions for resolving six p-nitroanilide peptides used as synthetic substrates of the elastolytic enzymes (human neutrophil elastase, cathepsin G, Pseudomonas aeruginosa elastase) most commonly involved in pulmonary diseases, we investigated the efficiency of ionic and nonionic surfactants in achieving the separation of this complex mixture. The results presented here show that, of all the electrophoretic systems tested, 30 mM sodium tetraborate, pH 9.3, containing 25 mM Brij 35 as micellar agent offered the best performance; the separation efficiency of peptides is greater than that obtained with other reagents and all peaks are baseline resolved and unambiguously identifiable. Analysis of the micelle-solute interaction with the surfactants investigated allowed better definition of the mechanism involved in the distribution of these peptides to the micelles and identification of some structural features that determined the magnitude of the micelle peptide complex formation.
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Affiliation(s)
- A Lupi
- Laboratorio di Biochimica e Genetica Clinica di Malattie dellApparato Respiratorio, IRCCS Policlinico San Matteo, Pavia, Italy
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Viglio S, Iadarola P, Lupi A, Trisolini R, Tinelli C, Balbi B, Grassi V, Worlitzsch D, Döring G, Meloni F, Meyer KC, Dowson L, Hill SL, Stockley RA, Luisetti M. MEKC of desmosine and isodesmosine in urine of chronic destructive lung disease patients. Eur Respir J 2000; 15:1039-45. [PMID: 10885422 DOI: 10.1034/j.1399-3003.2000.01511.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Degradation of extracellular matrix components is central to many pathological features of chronic destructive lung disorders. Desmosine and isodesmosine are elastin-derived cross-linked amino acids whose urine levels are considered representative of elastin breakdown. The aim of this study was to apply a novel methodology, based on high-performance capillary electrophoresis, to the quantification of desmosine and isodesmosine in 11 patients with stable chronic obstructive pulmonary disease (COPD), 10 with an exacerbation of COPD, nine with alpha1-antitrypsin deficiency, 13 with bronchiectasis, and 11 adults with cystic fibrosis, in comparison to 24 controls. It was found that, in patients with stable COPD, urinary desmosine levels were higher than in controls (p=0.03), but lower than in COPD subjects with an exacerbation (p< or =0.05). The highest desmosine levels were found in subjects with alpha1-antitrypsin deficiency, bronchiectasis and cystic fibrosis (p<0.001 versus stable COPD). In a short-term longitudinal study, five stable COPD patients showed a constant rate of desmosine excretion (mean coefficient of variation <8% over three consecutive days). In conclusion, the present method is simple and suitable for the determination of elastin-derived cross-linked amino acid excretion in urine, giving results similar to those obtained using other separation methods. In addition, evidence is presented that urinary desmosine excretion is increased in conditions characterized by airway inflammation, such as exacerbations of chronic obstructive pulmonary disease, bronchiectasis and cystic fibrosis. Results obtained in subjects with alphal-antitrypsin deficiency suggest that this method might be used to evaluate the putative efficacy of replacement therapy.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochemical, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San matteo, Università degli nStudi di Pavia
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Aquilani R, Viglio S, Iadarola P, Guarnaschelli C, Arrigoni N, Fugazza G, Catapano M, Boschi F, Dossena M, Pastoris O. Peripheral plasma amino acid abnormalities in rehabilitation patients with severe brain injury. Arch Phys Med Rehabil 2000; 81:176-81. [PMID: 10668771 DOI: 10.1016/s0003-9993(00)90137-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Acute severe brain injury causes an increased mobilization of amino acids from tissue. The plasma amino acid profile of patients undergoing rehabilitation after brain injury is unknown. This study was aimed at delineating the plasma amino acid profile of rehabilitation patients with brain injury. DESIGN Peripheral plasma aminogram, lactate, pyruvate, glycerol, ketone body, and carnitine concentrations were determined in 11 patients with brain injury (34.6+/-15 years old, 60+/-16.8 days after injury) and in 8 controls. Resting energy expenditure and nitrogen balance were also determined. RESULTS (1) All essential amino acids and about 50% of nonessential amino acids were significantly lower in brain injury patients than in controls (p < .05). (2) Plasma amino acids were lower irrespective of either energy and protein intake or nitrogen balance. (3) Total carnitine concentration and esterified/free carnitine ratio were higher in brain injury patients than in controls (p < .05). CONCLUSIONS Rehabilitation patients with brain injury may have an important reduction of their plasma aminogram. Muscle tissue depletion and the persistence of a hypercatabolic state caused by subclinical infections, pressure sores, and immobility may contribute to this reduction.
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Affiliation(s)
- R Aquilani
- Service of Metabolic and Nutritional Pathophysiology, S. Maugeri Foundation, IRCCS-Montescano, Italy
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Viglio S, Valentini G, Chiarelli L, Zanaboni G, Cetta G, Iadarola P. Micellar electrokinetic chromatography as a complementary method to sodium dodecyl sulfate-polyacrylamide gel electrophoresis for studying limited proteolysis of proteins. Electrophoresis 1999; 20:2400-6. [PMID: 10499331 DOI: 10.1002/(sici)1522-2683(19990801)20:12<2400::aid-elps2400>3.0.co;2-t] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Micellar electrokinetic chromatography (MEKC) has been utilized as an analytical method to perform investigations on limited proteolysis of proteins. To this purpose partial proteolysis experiments with a series of proteinases were performed, utilizing as model protein pyruvate kinase (PK) from Escherichia coli, an enzyme that is regulated allosterically by fructose 1,6-bisphosphate (FBP). Data obtained with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and MEKC were compared; the profiles generated by submitting digests of PK treated with different proteinases in the presence and absence of FBP to electrophoretic analysis provided a useful adjunct for a better understanding of the effects of the allosteric activator on the conformation of the model enzyme. MEKC was also found to be a convenient technique for determining the kinetics of substrate proteolysis.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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22
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Viglio S, Luisetti M, Zanaboni G, Döring G, Worlitzsch D, Cetta G, Iadarola P. Simultaneous determination of Pseudomonas aeruginosa elastase, human leukocyte elastase and cathepsin G activities by micellar electrokinetic chromatography. J Chromatogr A 1999; 846:125-34. [PMID: 10420604 DOI: 10.1016/s0021-9673(98)01056-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Micellar electrokinetic chromatography (MEKC) is a new method for analysing proteolytic activities simultaneously present in incubation mixtures. Here we demonstrate that MEKC differentiates between the enzymatic activities of Pseudomonas aeruginosa elastase (PsE) and human leukocyte elastase (HLE) or cathepsin G (Cat G) in assays using the chromogenic peptide substrates Suc-Ala-Ala-Ala-NA or Suc-Ala-Ala-Pro-Phe-NA, respectively (where Suc = succinyl and NA = 4-nitroaniline/u-nitroanilide). When PsE and Cat G were incubated at equimolar ratio with Suc-Ala-Ala-Pro-Phe-NA, the PsE-specific cleavage products PheNA and Suc-Ala-Ala-Pro were detected whereas inhibition of the metalloproteinase PsE with EDTA resulted in detection of NA and Suc-Ala-Ala-Pro-Phe only. Similarly, when PsE and HLE were incubated at equimolar ratio with Suc-Ala-Ala-Ala-NA, the PsE-specific cleavage products Suc-Ala and Ala-Ala-NA were detected whereas at an PsE-HLE ratio 1:50, both the PsE-specific and the HLE-specific cleavage products NA and Suc-Ala-Ala-Ala were separated. MEKC also allowed determination of the kinetic constants for the interactions of PsE, Cat G and HLE with the substrates considered.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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23
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Viglio S, Zanaboni G, Lupi A, Gianelli L, Luisetti M, Casali L, Cetta G, Iadarola P. Micellar electrokinetic chromatography for analyzing active site specificity of Pseudomonas aeruginosa elastase. Electrophoresis 1999; 20:1578-85. [PMID: 10424483 DOI: 10.1002/(sici)1522-2683(19990601)20:7<1578::aid-elps1578>3.0.co;2-u] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The geometry of the catalytic site of Pseudomonas aeruginosa elastase was reexamined, exploiting the specific feature of micellar electrokinetic chromatography (MEKC), i.e., its ability to detect a decrease of intact substrate and simultaneous formation of reaction products. We carried out a detailed investigation using two tri- and six tetra-peptide 4-nitroanilides (NA) differing from each other by only one or more amino acids as stable substrates. The kinetic cleavage parameters Km and k(cat) determined by MEKC and the catalytic efficiency Km/k(cat) values calculated allowed us to better define the substrate specificity of this proteinase.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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24
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Abstract
A quantitative ultraviolet detection method for determining ornithine transcarbamylase (OTC-ase) activity using micellar electrokinetic chromatography (MEKC) is described. The method is based on the direct determination of citrulline formed upon enzymatic reaction. Using a background electrolyte consisting of 35 mM sodium tetraborate, pH 9.3, containing 65 mM sodium dodecyl sulfate (SDS), the peak of citrulline in the electropherogram was easily identified and integrated. This allowed us to determine the rate of formation of the reaction product and to calculate the kinetic parameter Km of the OTC-ase investigated. The capillary electrophoretic method developed was applied to the determination of OTC-ase activity in plasma samples for citrulline in the nanogram range.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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25
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Viglio S, Zanaboni G, Luisetti M, Cetta G, Guglielminetti M, Iadarola P. Micellar electrokinetic chromatography: a convenient alternative to colorimetric and high performance liquid chromatographic detection to monitor protease activity. Electrophoresis 1998; 19:2083-9. [PMID: 9761185 DOI: 10.1002/elps.1150191207] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
High performance capillary electrophoresis (HPCE) has been exploited as an analytical method alternative to current procedures for the determination of proteolytic activity of elastases from different sources. Due to some drawbacks with capillary zone electrophoresis (CZE), the mode of operation employed for the assay of elastolytic activity was micellar electrokinetic chromatography (MEKC). Using a background electrolyte consisting of 35 mM sodium tetraborate, pH 9.3, containing 65 mM SDS and 15% v/v methanol, separation of intact peptide substrate from products of proteolytic reaction was easily achieved in a fused-silica capillary of 50 cm effective length x 75 microm ID. This allowed us to determine the rate of hydrolysis of substrates and to calculate the kinetic parameters Km and k(cat) of the proteases investigated. A comparison of these data with those obtained from high performance liquid chromatography (HPLC)-based experiments showed that MEKC is a convenient technique for studying protease kinetics.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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26
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Viglio S, Zanaboni G, Luisetti M, Trisolini R, Grimm R, Cetta G, Iadarola P. Micellar electrokinetic chromatography for the determination of urinary desmosine and isodesmosine in patients affected by chronic obstructive pulmonary disease. J Chromatogr B Biomed Sci Appl 1998; 714:87-98. [PMID: 9746238 DOI: 10.1016/s0378-4347(98)00046-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The presence in urine of desmosine (DES) and isodesmosine (IDES), two crosslinked amino acids unique to the elastic fiber network, can be used as a specific indicator of degradation of mature elastin. Compared to methodologies so far available, the capillary electrophoretic technique reported here seems to be suitable and convenient for determining desmosines in urine of patients affected by chronic obstructive pulmonary disease (COPD). By using 35 mM sodium tetraborate pH 9.3 containing 65 mM SDS as the background electrolyte, the peaks of DES and IDES could be detected in hydrolyzed urine samples from controls and patients. Owing to the simultaneous determination of endogenous urinary creatinine used as appropriate internal standard, the amount of these amino acids could be accurately quantified. The results obtained were of the same order of magnitude as the data already reported in the literature for COPD patients. Thus micellar electrokinetic chromatography (MEKC) may be considered as a reliable technique for studying the turnover of the elastic fiber in clinical conditions.
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Affiliation(s)
- S Viglio
- Dipartimento di Biochimica A. Castellani, Università di Pavia, Italy
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27
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Iadarola P, Lungarella G, Martorana PA, Viglio S, Guglielminetti M, Korzus E, Gorrini M, Cavarra E, Rossi A, Travis J, Luisetti M. Lung injury and degradation of extracellular matrix components by Aspergillus fumigatus serine proteinase. Exp Lung Res 1998; 24:233-51. [PMID: 9635248 DOI: 10.3109/01902149809041532] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Aspergillus fumigatus produces a variety of extracellular proteinases that are believed to be virulence factors towards Aspergillus-related lung disease. Among Aspergillus proteinases, the serine proteinase is thought to play a major virulent role because of its widespread production. Nevertheless, evidence of direct pulmonary injury caused by the A. fumigatus serine proteinase is still lacking. The purpose of our work was: (1) to provide evidence for a pivotal role of A. fumigatus serine proteinase in producing lung injury in an animal model, and (2) to investigate the broadness of the substrate specificity of the proteinase towards extracellular matrix components. To achieve this aim, the proteinase from an A. fumigatus strain isolated from human airways was purified by a four-step procedure, including cation exchange and hydrophobic interaction. High-performance capillary electrophoresis, SDS-PAGE, determination of K(m) towards synthetic substrates, and inhibitory studies were used to further characterize the A. fumigatus serine proteinase. With reference to extracellular matrix components, the A. fumigatus serine proteinase was shown to degrade human lung elastin at a higher rate than an equimolar amount of human neutrophil elastase. Human lung collagen, type I and type III collagens, as well as fibronectin, were quickly digested by the A. fumigatus serine proteinase. Finally, mice intratracheally injected with the proteinase showed a significant degree of lower respiratory tract destruction. We conclude that the A. fumigatus serine proteinase is capable per se of hydrolyzing the major structural barriers of the lung.
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Affiliation(s)
- P Iadarola
- Dipartimento di Biochimica, IRCCS Policlinico San Matteo, Pavia, Italy
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28
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Grimm R, Zanaboni G, Viglio S, Dyne KM, Cetta G, Iadarola P. Effect of different surfactants on the separation by micellar electrokinetic chromatography of a complex mixture of dipeptides in urine of prolidase-deficient patients. J Chromatogr B Biomed Sci Appl 1997; 698:47-57. [PMID: 9367192 DOI: 10.1016/s0378-4347(97)00309-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Prolidase deficiency is a severe disorder characterized by massive excretion of metabolites with closely related structures. At present, micellar electrokinetic chromatography is the separation method which provides the highest selectivity of structurally similar solutes. However, the structure of a surfactant can greatly affect the selectivity of separation depending on factors such as the length of hydrophobic alkyl chain or the nature of the hydrophilic group. Here we investigated the effect of three non-ionic and four anionic detergents for obtaining the best separation conditions for resolving imidodipeptide mixtures. The effect on resolution of variables such as temperature, surfactant concentrations and organic solvents was also examined. The greatest resolution was obtained at the lowest temperature studied (10 degrees C) using 50 mM sodium borate, pH 9.3 containing 50 mM pentanesulfonate and 10% (v/v) methanol. Under these experimental conditions almost all excreted components were baseline separated and identified.
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Affiliation(s)
- R Grimm
- Analytical Division, Hewlett-Packard, Waldbronn, Germany
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29
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Zanaboni G, Viglio S, Dyne KM, Grimm R, Valli M, Cetta G, Iadarola P. Direct monitoring of prolidase activity in cultured skin fibroblasts using capillary electrophoresis. J Chromatogr B Biomed Sci Appl 1997; 695:77-84. [PMID: 9271131 DOI: 10.1016/s0378-4347(96)00532-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Capillary electrophoresis (CE) was used as an alternative to current analysis schemes for detecting prolidase activity in erythrocytes and skin fibroblast cultures because of its unique selectivity and high resolving power. Kinetic measurement of peptide bond hydrolysis was performed using porcine kidney prolidase on different substrates (Gly-Pro, Leu-Pro and Ala-Pro) and by following the disappearance of the peptide-substrate's peak. The K(m) values obtained were in agreement with those previously reported. Interestingly, in the case of Phe-Pro as the substrate, simultaneous analysis of the product and parent peptide was possible, thus showing the superiority of the capillary electrophoresis (CE) assay with respect to the standard spectrophotometric method. The application of the CE technique to the characterization of prolidase activity in control and prolidase-deficient skin cultured fibroblasts was successful. Enzyme activity was easily calculated in all controls tested and the K(m) values determined were slightly lower than those obtained with the colorimetric reaction, thus confirming our assumption that the CE assay shows higher specificity than the ninhydrin technique. Our results demonstrate the feasibility of using CE as a simple and reliable technique for determining prolidase activity.
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Affiliation(s)
- G Zanaboni
- Dipartimento di Biochimica, Università di Pavia, Italy
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30
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Grimm R, Zanaboni G, Viglio S, Dyne K, Valli M, Cetta G, Iadarola P. Complete resolution of imidodipeptide mixtures in urine of prolidase-deficient patients using micellar electrokinetic chromatography. J Chromatogr A 1997; 768:57-66. [PMID: 9175275 DOI: 10.1016/s0021-9673(96)00983-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The use of capillary zone electrophoresis as an efficient method for the identification of urinary imidodipeptides of prolidase-deficient patients has already been reported. However, owing to the complexity of the components excreted, the resolution of electrophoretic patterns obtained was poor. Here we examine the use of micellar electrokinetic chromatography to enhance peak resolution in order to obtain better insight into the electropherograms of patients' urine. The usefulness of sodium dodecyl sulphate as surfactant is reported: refined electropherograms were achieved using 35 mM sodium borate, pH 8.3 containing 65 mM sodium dodecyl sulphate. Almost all peaks were baseline separated, collected and sequenced. This allowed us to define the exact imidodipeptide composition of patients' urine. The possibility of identifying and thus quantifying each single peak means that comparison of urinary imidodipeptide excretion patterns from different patients can be made and the hypothesis that peptide patterns can be correlated with differing clinical severity can be investigated.
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Affiliation(s)
- R Grimm
- Analytical Division, Hewlett-Packard GmbH, Waldbronn, Germany
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31
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Zanaboni G, Grimm R, Dyne KM, Rossi A, Cetta G, Iadarola P. Use of capillary zone electrophoresis for analysis of imidodipeptides in urine of prolidase-deficient patients. J Chromatogr B Biomed Appl 1996; 683:97-107. [PMID: 8876444 DOI: 10.1016/0378-4347(95)00583-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Prolidase deficiency (PD) is characterized by massive urinary excretion of imidodipeptides X-Pro and X-Hyp. We report the applicability of capillary zone electrophoresis to urinary imidodipeptide determination. The protocol is fast, simple, reliable, only small amounts of sample are required and there is minimal sample preparation. Electropherograms of urine samples from control subjects and four patients with prolidase deficiency were compared. The presence of imidodipeptides normally absent in urine was evident in patients' urine. Further analysis of urine samples enabled identification of excreted imidodipeptides and the pattern of excretion appeared to be heterogeneous for different patients. This method appears to be useful for identification of imidodipeptides in biological samples, as an efficient aid in diagnosis of PD, and as a method for providing more information about this disease.
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Affiliation(s)
- G Zanaboni
- Dipartimento di Biochimica, Università di Pavia, Italy
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32
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Valentini G, De Gregorio A, Di Salvo C, Grimm R, Bellocco E, Cuzzocrea G, Iadarola P. An essential lysine in the substrate-binding site of ornithine carbamoyltransferase. Eur J Biochem 1996; 239:397-402. [PMID: 8706746 DOI: 10.1111/j.1432-1033.1996.0397u.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Treatment of ornithine carbamoyltransferase from dolphin Stenella with pyridoxal phosphate, followed by reduction with NaBH4 resulted in complete loss of enzyme activity. The phosphate alone or the substrate analogue 2-aminovaleric acid moderately decreased the extent of inactivation, while carbamoyl phosphate plus 2-aminovaleric acid provided complete protection from inactivation. The partially inactivated enzyme showed K(m) values for substrates equivalent to those of native enzyme and lowered Kcat values. Two lysyl residues were substantially modified in the absence of ligands but only one of them was responsible for the inactivation of catalytic activity. Modification of a single subunit was sufficient to completely abolish the catalytic activity of the trimeric enzyme. The lysine involved has been identified as lysine 56 on the known primary structure of homologous human liver enzyme.
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Affiliation(s)
- G Valentini
- Dipartimento di Biochimica, Università di Pavia, Italy
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33
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Valentini G, Iadarola P, Ferri G, Speranza ML. Affinity labelling of the catalytic and allosteric ATP binding sites on pyruvate kinase type I from Escherichia coli. Biol Chem Hoppe Seyler 1995; 376:231-5. [PMID: 7626232 DOI: 10.1515/bchm3.1995.376.4.231] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The allosterically regulated pyruvate kinase type I (PKI) from E. coli was inactivated by the ATP analog 2',3'-dialdehyde ATP (o-ATP) with a Ki of 3.6 mM. ATP and phosphoenolpyruvate protected the enzyme activity while the allosteric activator fructose 1,6-bisphosphate enhanced the rate of inactivation. Incubation with o-ATP, followed by reduction of the formed Schiff bases with radioactive sodium borohydride, was employed to determine the ATP binding sites of PKI. After tryptic digestion, the purification of the labelled peptides and the sequence analysis allowed to identify four modified lysyl residues, namely Lys173, Lys175, Lys272, and Lys317 of the known DNA-deduced sequence of PKI. The close lysines 173 and 175 reacted with o-ATP in a mutually exclusive way and accounted together for 53% of the recovered radioactivity, the rest being distributed on Lys272 (31%) and Lys317 (16%). When fitted on the available three-dimensional structure of muscle pyruvate kinase, the position of the modified lysines defines both the catalytic and the allosteric ATP binding sites on PKI.
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Affiliation(s)
- G Valentini
- Dipartimento di Biochimica, Università di Pavia, Italy
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34
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35
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Moretti M, Gorrini M, Donnetta AM, Baldini EV, Venturini R, Marchioni CF, Iadarola P, Luisetti M. Effects of MR889, a cyclic thiolic neutrophil elastase inhibitor, on rheologic properties of mucus. Life Sci 1994; 54:463-9. [PMID: 8309349 DOI: 10.1016/0024-3205(94)00405-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
MR889 is a synthetic inhibitor of human neutrophil elastase with potential in clinical conditions characterized by a high load of this proteolytic enzyme, mainly chronic obstructive pulmonary disease. On the basis of its mechanism of inhibition, it has been suggested that MR889, upon reaction with elastase, would generate new free thiol groups. The aim of this study was to investigate whether MR889, upon reaction with elastase, may modify rheologic properties, i.e. apparent viscosity and elasticity, of both human sputum and porcine stomach mucus, in ex-vivo and in vitro experiments. MR889 10(-4) M alone had no effect on rheologic properties of samples, whereas an agent with free thiol group, n-acetylcysteine 10(-4) M reduced both viscosity and elasticity. MR889 10(-4) M upon reaction with elastase 0.03 nMol (giving 83% of elastase inhibition) had no effect on rheologic properties of samples, whereas upon reaction with elastase 0.15 nMol (49% inhibition) yielded a marked decrease in viscosity. This result would suggest that MR889, in the presence of a high load of elastase, may acquire direct mucus modifying capacity, likely because of its greater utilization upon reaction with the enzyme.
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Affiliation(s)
- M Moretti
- Istituto di Tisiologia e Malattie dell'Apparato Respiratorio, Università di Modena, Italy
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36
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Galliano M, Minchiotti L, Iadarola P, Stoppini M, Giagnoni P, Watkins S, Madison J, Putnam FW. Protein and DNA sequence analysis of a 'private' genetic variant: albumin Ortonovo (Glu-505-->Lys). Biochim Biophys Acta 1993; 1225:27-32. [PMID: 7902134 DOI: 10.1016/0925-4439(93)90117-j] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Albumin Ortonovo is a slow moving variant of human serum albumin which has been found only in people coming from the small villages of Ortonovo and Nicola (Liguria, Italy) and reaches polymorphic frequency (> or = 1%) in the poorly admixed population group living in that area. This is the first report of a 'private' variant detected in a Caucasian population. It probably originated as a mutation in a founder individual many generations ago. Isoelectric focusing analysis of CNBr fragments from the purified variant localized the mutation in fragment CNBr VI (residues 447-548). This fragment was isolated on a preparative scale by reversed-phase HPLC and subjected to V8 proteinase digestion. Sequence analysis of the abnormal V8 peptide revealed that the variant arises from a previously unreported substitution at position 505 where glutamic acid has been replaced by lysine. The protein data were confirmed by DNA sequence analysis which indicated a single nucleotide change of GAA-->AAA in the corresponding codon of the structural gene. Since the amino acid substitution found in albumin Ortonovo accords with its electrophoretic mobility on cellulose acetate, residue 505 is probably exposed to the solvent. The clustering of the mutations in the intersubdomain connection linking subdomains IIIA and IIIB (residues 492-511) accords with the fact that this region lies on the molecular surface and is accessible to solvent.
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Affiliation(s)
- M Galliano
- Istituto di Biologia Applicata, Università di Sassari, Italy
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37
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Zapponi MC, Iadarola P, Stoppini M, Ferri G. Limited proteolysis of chloroplast glyceraldehyde-3-phosphate dehydrogenase (NADP) from Spinacia oleracea. Biol Chem Hoppe Seyler 1993; 374:395-402. [PMID: 8357535 DOI: 10.1515/bchm3.1993.374.1-6.395] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The structural and functional properties of chloroplast glyceraldehyde-3-P-dehydrogenase I (D-Glyceraldehyde-3-phosphate: NADP oxidoreductase (phosphorylating) EC 1.2.1.13) from Spinacia oleracea were investigated by limited proteolysis. The enzyme is insensitive to trypsin and chymotrypsin, while Staphylococcus aureus V8 protease cleaves the C-terminal region of its subunits. Subunit A (36 kDa) is only partially cleaved at Glu 317. No intact subunit B (39 kDa) is found at the end of the proteolytic experiment: two forms are originated from this subunit which is cleaved at Glu 342 and Glu 320. Proteolytic cleavage at these sites does not significantly alter enzymatic activity, but leads to destabilization of the protein. Unlike the intact parent enzyme (600 kDa) the cleaved enzyme behaves as a 150-kDa species in size exclusion chromatography.
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Affiliation(s)
- M C Zapponi
- Dipartimento di Biochimica, Università di Pavia, Italia
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38
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Guglielminetti M, Piccioni P, Iadarola P, Luisetti M, Caretta G. Production of serine chymotrypsin-like elastase by Aspergillus fumigatus strains. ACTA ACUST UNITED AC 1993. [DOI: 10.22370/bolmicol.1993.8.0.1152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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39
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Valentini G, Stoppini M, Iadarola P, Malcovati M, Ferri G, Speranza ML. Divergent binding sites in pyruvate kinases I and II from Escherichia coli. Biol Chem Hoppe Seyler 1993; 374:69-74. [PMID: 8439398 DOI: 10.1515/bchm3.1993.374.1-6.69] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Pyridoxal 5'-phosphate incorporation into pyruvate kinase II from E. coli was decreased by the substrate phosphoenolpyruvate and increased by the allosteric activator ribose 5-phosphate, the total incorporation being linearly related to inactivation. Four lysyl residues were substantially modified, whatever the incubation conditions were while two additional residues became reactive only in the presence of the allosteric activator. Six tryptic peptides containing modified lysines were purified and sequenced. They defined five regions of pyruvate kinase II, since one of them contained two labelled lysines and included a peptide which also appeared independently. Sequence comparison with E. coli type I, yeast and cat muscle pyruvate kinases shows that the binding regions of pyruvate kinase II are clearly divergent from those of pyruvate kinase I and of the eukaryotic enzymes.
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Affiliation(s)
- G Valentini
- Dipartimento di Biochimica, Università di Pavia
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40
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Ferri G, Stoppini M, Meloni ML, Zapponi MC, Iadarola P. Chloroplast glyceraldehyde-3-phosphate dehydrogenase (NADP): amino acid sequence of the subunits from isoenzyme I and structural relationship with isoenzyme II. Biochim Biophys Acta 1990; 1041:36-42. [PMID: 2223845 DOI: 10.1016/0167-4838(90)90119-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The structural relationship between isoenzymes I and II of chloroplast glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate: NADP+ oxidoreductase (phosphorylating) EC 1.2.1.13) has been established at the protein level. The complete primary structure of subunits A and B of glyceraldehyde-3-phosphate dehydrogenase I from Spinacia oleracea has been determined by sequence analysis of the corresponding tryptic peptides, aligned by fragments derived from cyanogen bromide and Staphylococcus proteinase V8 digestions and by partially sequencing each intact subunit. Subunit A has an Mr of 36,225 and consists of 337 amino acid residues, whilst subunit B (Mr 39,355) consists of 368 residues. The amino acid sequence of subunit B, as determined through direct analysis of the protein, is identical to that recently deduced at cDNA level (Brinkmann et al. (1989) Plant Mol. Biol. 13, 81-94). The two subunits share a common portion of amino acid sequence which differs by 66 amino acid residues. Subunit B has an extra C-terminal sequence of 31 amino acid residues. Chloroplast glyceraldehyde-3-phosphate dehydrogenase II was partially characterized by sequencing the N-terminal portion of the intact protein and some of its tryptic peptides. The sequences of all the examined fragments fit precisely that of the corresponding regions of subunit A from glyceraldehyde-3-phosphate dehydrogenase I.
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Affiliation(s)
- G Ferri
- Department of Biochemistry, University of Pavia, Italy
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41
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Iadarola P, Zapponi MC, Minchiotti L, Meloni ML, Galliano M, Ferri G. Separation of fragments from human serum albumin and its charged variants by reversed-phase and cation-exchange high-performance liquid chromatography. J Chromatogr A 1990; 512:165-76. [PMID: 2229226 DOI: 10.1016/s0021-9673(01)89483-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Reversed-phase high-performance liquid chromatography (RP-HPLC) and ion-exchange chromatography on poly(2-sulphoethylaspartamide)-silica (SCX) were compared as alternative approaches in characterizing charged genetic variants of human serum albumin. The chromatographic behaviour of cyanogen bromide (CNBr), tryptic and V8 protease digests from normal and mutant albumins were examined. The results showed that substituted site-containing CNBr fragments are successfully resolved by RP-HPLC; in most instances SCX and RP-HPLC are equally adequate in identifying the modified tryptic peptides from CNBr fragments; although generally useful, SCX chromatography is specifically needed in all instances where amino acid replacement is occurring in a small hydrophilic tryptic fragment and choosing Staphylococcus aureus V8 protease instead of tryptic digestion is advantageous.
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Affiliation(s)
- P Iadarola
- Dipartimento di Biochimica, Università di Pavia, Italy
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42
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Abstract
Albumin Castel di Sangro is a rare fast-moving variant of human serum albumin which has been discovered in heterozygous form in the serum of an 85-year-old woman living in Castel di Sangro (Abruzzo, Italy). Isoelectric focusing analysis of CNBr fragments from the purified variant allowed us to localize the mutation in fragment CNBr VI (residues 447-548). This fragment was isolated on a preparative scale and subjected to tryptic digestion. Sequential analysis of the abnormal tryptic peptide, purified by reverse-phase and cation-exchange HPLC, revealed that the variant arises from the substitution of lysine 536 by glutamic acid. This amino acid replacement, probably due to a single-base substitution in the structural gene, causes a change in the net charge of -2 units, which is in keeping with both the increased electrophoretic mobility of the native protein and the isoelectric point of the modified CNBr fragment.
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Affiliation(s)
- L Minchiotti
- Dipartimento di Biochimica, Università, Pavia, Italy
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43
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Carbonera D, Iadarola P, Cella R. Effect of exogenous amino acids on the intracellular content of proline and other amino acids in Daucus carota cells. Plant Cell Rep 1989; 8:422-424. [PMID: 24233368 DOI: 10.1007/bf00270084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/1989] [Revised: 09/20/1989] [Indexed: 06/02/2023]
Abstract
The effect of tryptophan on the biosynthesis of proline has been investigated. Cells of Daucus carota grown in B5 medium supplemented with 5×10(-4)M tryptophan acquired the ability to grow in the presence of inhibitory concentrations of azetidine-2-carboxylic acid, an analog of proline. When trp was added to carrot cell cultures at sub-growth inhibiting concentrations, overproduction of intracellular free proline was observed. An increase was also observed for lys, his, ala, leu and phe. Likewise, the addition of asparagine, glutamic acid and phenylalanine to the medium stimulated the intracellular increase of free proline and other amino acids.
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Affiliation(s)
- D Carbonera
- Dipartimento di Genetica e Microbiologia "A. Buzzati Traverso", Università di Pavia, Via S. Epifanio 14, I-27100, Pavia, Italy
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Galliano M, Minchiotti L, Iadarola P, Stoppini M, Porta F, Castellani AA. Molecular defects in genetic variants of human serum albumin. Ital J Biochem 1989; 38:292A-293A. [PMID: 2583984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- M Galliano
- Dipartimento di Biochimica, Università di Pavia
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45
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Ferri G, Stoppini M, Iadarola P, Bellotti V, Merlini G. Structural characterization of kappa II Inc, a new amyloid immunoglobulin. Biochim Biophys Acta 1989; 995:103-8. [PMID: 2495028 DOI: 10.1016/0167-4838(89)90067-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Light chain Inc, obtained from a patient with amyloid arthropathy, has an Mr of 23,550 and consists of 219 amino acid residues. The complete primary structure of its variable domain has been determined by sequence analysis of the corresponding tryptic peptides, aligned by fragments derived from cyanogen bromide digestion, and by partially sequencing the intact protein. Although closely related to protein of the V kappa II subgroup, light chain Inc differs from its counterpart by the replacement of some invariant residues in its variable domain. By comparing its sequence with that of the nonamyloid kappa II Nim, a different distribution of some polar and apolar amino acid residues through the molecule is evidenced. A computer graphic analysis shows that some of the replaced amino acid residues cannot be readily accommodated in the known three-dimensional structure of the immunoglobulin light chains.
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Affiliation(s)
- G Ferri
- Department of Biochemistry, Scientific Institute, San Matteo, University of Pavia, Italy
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46
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Speranza ML, Valentini G, Iadarola P, Stoppini M, Malcovati M, Ferri G. Primary structure of three peptides at the catalytic and allosteric sites of the fructose-1,6-bisphosphate-activated pyruvate kinase from Escherichia coli. Biol Chem Hoppe Seyler 1989; 370:211-6. [PMID: 2653362 DOI: 10.1515/bchm3.1989.370.1.211] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Three peptides containing 6-pyridoxyllysine have been isolated from the tryptic digest of the allosteric fructose-1,6-bisphosphate-dependent pyruvate kinase from Escherichia coli, which had been almost completely inactivated with pyridoxal 5'-phosphate. The labelled peptides have been sequenced. The comparison of their sequences with the primary structure of the cat muscle pyruvate kinase allowed to state that peptide I fits the region spanning residues 423-438 (53% identity), peptide II corresponds to residues 442-457 (44% identity) and peptide III encompasses residues 342-368 (70% identity). These findings are discussed in connection with our previous results on the involvement of the three peptides in the catalytic and regulatory properties of the enzyme (Valentini, G., Speranza, M.L., Iadarola, P., Ferri, G. & Malcovati, M. (1988) Biol. Chem. Hoppe-Seyler 369, 1219-1226) and in connection with their location in the three-dimensional structure of the cat muscle pyruvate kinase (Muirhead, H., Clayden, D.A., Lorimer, C.G., Fothergill-Gilmore, L.A., Schiltz, E. & Schmitt, W. (1986) EMBO J. 5, 475-481).
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Minchiotti L, Galliano M, Iadarola P, Meloni ML, Ferri G, Porta F, Castellani AA. The molecular defect in a COOH-terminal-modified and shortened mutant of human serum albumin. J Biol Chem 1989; 264:3385-9. [PMID: 2914956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Albumin Venezia is a fast migrating genetic variant of human serum albumin which, in heterozygous subjects, represents about 30% of the circulating protein. The molecular defect in this variant was studied in a subject possessing an atypical level of the mutant (80% of the total protein) and in other members of his family. Albumins, isolated from the sera of the propositus and his heterozygous relatives, were treated with CNBr and the resulting fragments analyzed by isoelectric focusing. The peptides were then isolated in a homogeneous form by reverse-phase high performance liquid chromatography and submitted to sequence analysis. The results show that albumin Venezia possesses a shortened polypeptide chain, 578 residues instead of 585, completely variant from residue 572 to the COOH-terminal end: sequence: (see text). This extensive modification may be accounted for by the deletion of exon 14 and translation to the first terminator codon of exon 15, which normally does not code for protein. The absence of a basic COOH-terminal dipeptide in the mature molecule can be explained by the probable action of serum carboxypeptidase N. Additional support for such action comes from examination of the remaining 20% of the total albumin of the propositus, which is found to contain an extra Arg at its COOH terminus, probably due to partial digestion by carboxypeptidase N. The low serum level of the variant in heterozygous subjects suggests that the COOH-terminal end of the molecule is critical for albumin stability.
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Affiliation(s)
- L Minchiotti
- Department of Biochemistry, University of Pavia, Italy
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48
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Minchiotti L, Galliano M, Iadarola P, Meloni ML, Ferri G, Porta F, Castellani AA. The Molecular Defect in a COOH-terminal-modified and shOrtened Mutant of Human Serum Albumin. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)94078-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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49
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Valentini G, Speranza ML, Iadarola P, Ferri G, Malcovati M. Reactivity of the fructose 1,6-bisphosphate-activated pyruvate kinase from Escherichia coli with pyridoxal 5'-phosphate. Biol Chem Hoppe Seyler 1988; 369:1219-26. [PMID: 3072970 DOI: 10.1515/bchm3.1988.369.2.1219] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The allosteric fructose 1,6-bisphosphate-activated pyruvate kinase from Escherichia coli was modified with pyridoxal 5'-phosphate in the presence and in the absence of phosphoenolpyruvate, fructose 1,6-bisphosphate, MgADP and MgATP. In all cases a time-dependent inactivation was observed, but the rate and the extent of inactivation varied according to the conditions used. The kinetic properties of the partially inactivated enzyme were differently modified by addition of substrates and effectors to the modification mixture, the parameters mostly affected being those concerning fructose 1,6-bisphosphate. Tryptic peptides obtained from fully inactivated pyruvate kinase in the different conditions have been separated. In all conditions three main 6-pyridoxyllysine-containing peptides were present, the amounts of which showed significant differences in the presence of fructose 1,6-bisphosphate and MgADP. The function of the labelled peptides and the evidence supporting the physical existence of different conformational states are discussed. The main conclusion concerns the involvement of one of the above peptides in the binding of the allosteric effector fructose 1,6-bisphosphate.
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Affiliation(s)
- G Valentini
- Dipartimento di Biochimica, Università di Pavia
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50
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Iadarola P, Zapponi MC, Stoppini M, Meloni ML, Minchiotti L, Galliano M, Ferri G. High-performance liquid chromatography of complex mixtures of cyanogen bromide-produced peptides from different proteins. J Chromatogr A 1988; 443:317-28. [PMID: 3170693 DOI: 10.1016/s0021-9673(00)94803-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A variety of approaches have been required in order to achieve the resolution of large fragments from cyanogen bromide (CNBr) digests of Inc k chain (an immunoglobulin light chain), human serum albumin (HSA) and four of its mutants. Reversed-phase high-performance liquid chromatography (RP-HPLC) under different conditions failed to resolve the Inc k chain digest; the three CNBr fragments (3.1, 6.7 and 13.7 kDa) were separated in a homogeneous form by gel HPLC. Five of the seven CNBr fragments (ranging from 3.4 to 20.0 kDa) obtained from CNBr cleavage of HSA can be resolved by a single reversed-phase HPLC step; separation of the other two requires modification of the eluent composition. Some structural features of the peptides seem to influence their chromatographic behaviour; by examining the elution patterns from albumin mutants, the sequence-related contribution of single amino acid residues is apparent.
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Affiliation(s)
- P Iadarola
- Dipartimento di Biochimica, Università di Pavia, Italy
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