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Li Z, Zhang L, Wang Z, Kang X, Jin H, Zhao W, Zhang J, Su H. Quantification of Phosphatidylserine Molecules on the Surface of Individual Cells Using Single-Molecule Force Spectroscopy. Anal Chem 2024; 96:676-684. [PMID: 38173079 DOI: 10.1021/acs.analchem.3c03517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Identification of the phosphatidylserine (PS) discrepancies occurring on the cellular membrane during apoptotic processes is of the utmost importance. However, monitoring the quantity of PS molecules in real-time at a single-cell level currently remains a challenging task. Here, we demonstrate this objective by leveraging the specific binding and reversible interaction exhibited by the zinc(II) dipyridinamine complex (ZnDPA) with PS. Lipoic acid-functionalized ZnDPA (LP-ZnDPA) was subsequently immobilized onto the surface of an atomic force microscopy cantilever to form a force probe, ALP-ZnDPA, enabling a PS-specific dynamic imaging and detection mode. By utilizing this technique, we can not only create a heat map of the expression level of PS with submicron resolution but also quantify the number of molecules present on a single cell's surface with a detection limit of 1.86 × 104 molecules. The feasibility of the proposed method is demonstrated through the analysis of PS expression levels in different cancer cell lines and at various stages of paclitaxel-induced apoptosis. This study represents the first application of a force probe to quantify PS molecules on the surface of individual cells, providing insight into dynamic changes in PS content during apoptosis at the molecular level and introducing a novel dimension to current detection methodologies.
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Affiliation(s)
- Zhirong Li
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Lulu Zhang
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Zhanzhong Wang
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Xiongli Kang
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Huiying Jin
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Wenjie Zhao
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Jun Zhang
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
| | - Haiquan Su
- Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, China
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2
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Moya F, Curstedt T, Johansson J, Sweet D. Synthetic surfactants. Semin Fetal Neonatal Med 2023; 28:101503. [PMID: 38036308 DOI: 10.1016/j.siny.2023.101503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Affiliation(s)
- Fernando Moya
- Division of Wilmington Pediatric Subspecialties, Department of Pediatrics, UNC School of Medicine, USA
| | - Tore Curstedt
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Jan Johansson
- Dept of Biosciences and Nutrition, Karolinska Institutet, Neo, 141 83, Huddinge Sweden
| | - David Sweet
- Regional Neonatal Unit, Royal Maternity Hospital, Grosvenor Road, Belfast, UK.
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3
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Mikolka P, Kronqvist N, Haegerstrand-Björkman M, Jaudzems K, Kosutova P, Kolomaznik M, Saluri M, Landreh M, Calkovska A, Curstedt T, Johansson J. Synthetic surfactant with a combined SP-B and SP-C analogue is efficient in rabbit models of adult and neonatal respiratory distress syndrome. Transl Res 2023; 262:60-74. [PMID: 37499744 DOI: 10.1016/j.trsl.2023.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/13/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023]
Abstract
Respiratory distress syndrome (RDS) in premature infants is caused by insufficient amounts of endogenous lung surfactant and is efficiently treated with replacement therapy using animal-derived surfactant preparations. On the other hand, adult/acute RDS (ARDS) occurs secondary to for example, sepsis, aspiration of gastric contents, and multitrauma and is caused by alveolar endothelial damage, leakage of plasma components into the airspaces and inhibition of surfactant activity. Instillation of surfactant preparations in ARDS has so far resulted in very limited treatment effects, partly due to inactivation of the delivered surfactants in the airspace. Here, we develop a combined surfactant protein B (SP-B) and SP-C peptide analogue (Combo) that can be efficiently expressed and purified from Escherichia coli without any solubility or purification tag. NMR spectroscopy shows that Combo peptide forms α-helices both in organic solvents and in lipid micelles, which coincide with the helical regions described for the isolated SP-B and SP-C parts. Artificial Combo surfactant composed of synthetic dipalmitoylphosphatidylcholine:palmitoyloleoylphosphatidylglycerol, 1:1, mixed with 3 weights % relative to total phospholipids of Combo peptide efficiently improves tidal volumes and lung gas volumes at end-expiration in a premature rabbit fetus model of RDS. Combo surfactant also improves oxygenation and respiratory parameters and lowers cytokine release in an acid instillation-induced ARDS adult rabbit model. Combo surfactant is markedly more resistant to inhibition by albumin and fibrinogen than a natural-derived surfactant in clinical use for the treatment of RDS. These features of Combo surfactant make it attractive for the development of novel therapies against human ARDS.
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Affiliation(s)
- Pavol Mikolka
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia; Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Nina Kronqvist
- Department of Biosciences and Nutrition, Karolinska Institutet, Neo, Huddinge, Sweden
| | - Marie Haegerstrand-Björkman
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Kristaps Jaudzems
- Department of Physical Organic Chemistry, Latvian Institute of Organic Synthesis, Riga, Latvia; Faculty of Chemistry, University of Latvia, Riga, Latvia
| | - Petra Kosutova
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Maros Kolomaznik
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Mihkel Saluri
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Calkovska
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Tore Curstedt
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Jan Johansson
- Department of Biosciences and Nutrition, Karolinska Institutet, Neo, Huddinge, Sweden.
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4
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Basabe-Burgos O, Landreh M, Rising A, Curstedt T, Jan Johansson. Treatment of Respiratory Distress Syndrome with Single Recombinant Polypeptides that Combine Features of SP-B and SP-C. ACS Chem Biol 2021; 16:2864-2873. [PMID: 34878249 DOI: 10.1021/acschembio.1c00816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Treatment of respiratory distress syndrome (RDS) with surfactant replacement therapy in prematurely born infants was introduced more than 30 years ago; however, the surfactant preparations currently in clinical use are extracts from animal lungs. A synthetic surfactant that matches the currently used nature-derived surfactant preparations and can be produced in a cost-efficient manner would enable worldwide treatment of neonatal RDS and could also be tested against lung diseases in adults. The major challenge in developing fully functional synthetic surfactant preparations is to recapitulate the properties of the hydrophobic lung surfactant proteins B (SP-B) and SP-C. Here, we have designed single polypeptides that combine properties of SP-B and SP-C and produced them recombinantly using a novel solubility tag based on spider silk production. These Combo peptides mixed with phospholipids are as efficient as nature-derived surfactant preparations against neonatal RDS in premature rabbit fetuses.
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Affiliation(s)
- Oihana Basabe-Burgos
- Department of Biosciences and Nutrition, Karolinska Institutet, Neo, 141 83 Huddinge, Sweden
| | - Michael Landreh
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Tomtebodavägen 23A, SE-171 65 Stockholm, Sweden
| | - Anna Rising
- Department of Biosciences and Nutrition, Karolinska Institutet, Neo, 141 83 Huddinge, Sweden
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, 751 23 Uppsala, Sweden
| | - Tore Curstedt
- Department of Molecular Medicine and Surgery, Karolinska Institutet at Karolinska University Hospital, 171 76 Stockholm, Sweden
| | - Jan Johansson
- Department of Biosciences and Nutrition, Karolinska Institutet, Neo, 141 83 Huddinge, Sweden
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5
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Basabe-Burgos O, Ahlström JZ, Mikolka P, Landreh M, Johansson J, Curstedt T, Rising A. Efficient delipidation of a recombinant lung surfactant lipopeptide analogue by liquid-gel chromatography. PLoS One 2019; 14:e0226072. [PMID: 31800629 PMCID: PMC6892477 DOI: 10.1371/journal.pone.0226072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/19/2019] [Indexed: 11/23/2022] Open
Abstract
Pulmonary surfactant preparations extracted from natural sources have been used to treat millions of newborn babies with respiratory distress syndrome (RDS) and can possibly also be used to treat other lung diseases. Due to costly production and limited supply of animal-derived surfactants, synthetic alternatives are attractive. The water insolubility and aggregation-prone nature of the proteins present in animal-derived surfactant preparations have complicated development of artificial surfactant. A non-aggregating analog of lung surfactant protein C, SP-C33Leu is used in synthetic surfactant and we recently described an efficient method to produce rSP-C33Leu in bacteria. Here rSP-C33Leu obtained by salt precipitation of bacterial extracts was purified by two-step liquid gel chromatography and analyzed using mass spectrometry and RP-HPLC, showing that it is void of modifications and adducts. Premature New Zealand White rabbit fetuses instilled with 200mg/kg of 2% of rSP-C33Leu in phospholipids and ventilated with a positive end expiratory pressure showed increased tidal volumes and lung gas volumes compared to animals treated with phospholipids only. This shows that rSP-C33Leu can be purified from bacterial lipids and that rSP-C33Leu surfactant is active against experimental RDS.
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Affiliation(s)
- Oihana Basabe-Burgos
- Department of Neurobiology, Care Sciences and Society, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Jakub Zebialowicz Ahlström
- Department of Neurobiology, Care Sciences and Society, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Pavol Mikolka
- Department of Neurobiology, Care Sciences and Society, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
- Biomedical Center Martin and Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Michael Landreh
- Science for Life Laboratory, Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Tomtebodavägen, Stockholm, Sweden
| | - Jan Johansson
- Department of Neurobiology, Care Sciences and Society, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Tore Curstedt
- Department of Molecular Medicine and Surgery, Karolinska Institutet at Karolinska University Hospital, Stockholm, Sweden
| | - Anna Rising
- Department of Neurobiology, Care Sciences and Society, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden
- * E-mail:
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6
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Johansson J, Curstedt T. Synthetic surfactants with SP-B and SP-C analogues to enable worldwide treatment of neonatal respiratory distress syndrome and other lung diseases. J Intern Med 2019; 285:165-186. [PMID: 30357986 DOI: 10.1111/joim.12845] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Treatment of neonatal respiratory distress syndrome (RDS) using animal-derived lung surfactant preparations has reduced the mortality of handling premature infants with RDS to a 50th of that in the 1960s. The supply of animal-derived lung surfactants is limited and only a part of the preterm babies is treated. Thus, there is a need to develop well-defined synthetic replicas based on key components of natural surfactant. A synthetic product that equals natural-derived surfactants would enable cost-efficient production and could also facilitate the development of the treatments of other lung diseases than neonatal RDS. Recently the first synthetic surfactant that contains analogues of the two hydrophobic surfactant proteins B (SP-B) and SP-C entered clinical trials for the treatment of neonatal RDS. The development of functional synthetic analogues of SP-B and SP-C, however, is considerably more challenging than anticipated 30 years ago when the first structural information of the native proteins became available. For SP-B, a complex three-dimensional dimeric structure stabilized by several disulphides has necessitated the design of miniaturized analogues. The main challenge for SP-C has been the pronounced amyloid aggregation propensity of its transmembrane region. The development of a functional non-aggregating SP-C analogue that can be produced synthetically was achieved by designing the amyloidogenic native sequence so that it spontaneously forms a stable transmembrane α-helix.
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Affiliation(s)
- J Johansson
- Department of Neurobiology, Care Sciences and Society, Section for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - T Curstedt
- Laboratory for Surfactant Research, Department of Molecular Medicine and Surgery, Karolinska Institutet at Karolinska University Hospital, Stockholm, Sweden
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7
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Harayama T, Shindou H, Kita Y, Otsubo E, Ikeda K, Chida S, Weaver TE, Shimizu T. Establishment of LC-MS methods for the analysis of palmitoylated surfactant proteins. J Lipid Res 2015; 56:1370-9. [PMID: 26022805 DOI: 10.1194/jlr.d060236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Indexed: 01/08/2023] Open
Abstract
The surfactant proteins (SPs), SP-B and SP-C, are important components of pulmonary surfactant involved in the reduction of alveolar surface tension. Quantification of SP-B and SP-C in surfactant drugs is informative for their quality control and the evaluation of their biological activity. Western blot analysis enabled the quantification of SP-B, but not SP-C, in surfactant drugs. Here, we report a new procedure involving chemical treatments and LC-MS to analyze SP-C peptides. The procedure enabled qualitative analysis of SP-C from different species with discrimination of the palmitoylation status and the artificial modifications that occur during handling and/or storage. In addition, the method can be used to estimate the total amount of SP-C in pulmonary surfactant drugs. The strategy described here might serve as a prototype to establish analytical methods for peptides that are extremely hydrophobic and behave like lipids. The new method provides an easy measurement of SP-C from various biological samples, which will help the characterization of various experimental animal models and the quality control of surfactant drugs, as well as diagnostics of human samples.
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Affiliation(s)
- Takeshi Harayama
- Department of Lipid Signaling, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Hideo Shindou
- Department of Lipid Signaling, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan CREST, Japan Science and Technology Agency, Kawaguchi-shi, Saitama 332-0012, Japan
| | - Yoshihiro Kita
- Department of Lipidomics, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Eiji Otsubo
- Department of Lipid Signaling, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan Advanced Medical Research Department, Research Division, Mitsubishi Tanabe Pharma Corporation, Yokohama-shi, Kanagawa 227-0033, Japan
| | - Kazushige Ikeda
- Division of Neonantology, Department of Pediatrics, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shoichi Chida
- Department of Pediatrics, School of Medicine, Iwate Medical University, Morioka-shi, Iwate 020-8505, Japan
| | - Timothy E Weaver
- Division of Pulmonary Biology, Medical Center, Cincinnati Children's Hospital, Cincinnati, OH 45229-3026
| | - Takao Shimizu
- Department of Lipid Signaling, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan Department of Lipidomics, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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8
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Trötschel C, Poetsch A. Current approaches and challenges in targeted absolute quantification of membrane proteins. Proteomics 2015; 15:915-29. [DOI: 10.1002/pmic.201400427] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/05/2014] [Accepted: 12/05/2014] [Indexed: 01/08/2023]
Affiliation(s)
| | - Ansgar Poetsch
- Department of Plant Biochemistry; Ruhr-University Bochum; Bochum Germany
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9
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Almlén A, Stichtenoth G, Linderholm B, Haegerstrand-Björkman M, Robertson B, Johansson J, Curstedt T. Surfactant proteins B and C are both necessary for alveolar stability at end expiration in premature rabbits with respiratory distress syndrome. J Appl Physiol (1985) 2008; 104:1101-8. [DOI: 10.1152/japplphysiol.00865.2007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Modified natural surfactant preparations, used for treatment of respiratory distress syndrome in premature infants, contain phospholipids and the hydrophobic surfactant protein (SP)-B and SP-C. Herein, the individual and combined effects of SP-B and SP-C were evaluated in premature rabbit fetuses treated with airway instillation of surfactant and ventilated without positive end-expiratory pressure. Artificial surfactant preparations composed of synthetic phospholipids mixed with either 2% (wt/wt) of porcine SP-B, SP-C, or a synthetic poly-Leu analog of SP-C (SP-C33) did not stabilize the alveoli at the end of expiration, as measured by low lung gas volumes of ∼5 ml/kg after 30 min of ventilation. However, treatment with phospholipids containing both SP-B and SP-C/SP-C33 approximately doubled lung gas volumes. Doubling the SP-C33 content did not affect lung gas volumes. The tidal volumes were similar in all groups receiving surfactant. This shows that SP-B and SP-C exert different physiological effects, since both proteins are needed to establish alveolar stability at end expiration in this animal model of respiratory distress syndrome, and that an optimal synthetic surfactant probably requires the presence of mimics of both SP-B and SP-C.
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10
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Almlén A, Stichtenoth G, Robertson B, Johansson J, Curstedt T. Concentration dependence of a poly-leucine surfactant protein C analogue on in vitro and in vivo surfactant activity. Neonatology 2007; 92:194-200. [PMID: 17476119 DOI: 10.1159/000102057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Accepted: 01/10/2007] [Indexed: 11/19/2022]
Abstract
BACKGROUND Modified natural surfactants currently used for treatment of respiratory distress syndrome contain about 0.5-1% (w/w phospholipids) of each of the surfactant proteins SP-B and SP-C. The supply of these preparations is limited and synthetic surfactant preparations containing lipids and peptides are under development. OBJECTIVES To investigate the potential of different concentrations of the SP-C analogue SP-C33 in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (68:31, w/w). METHODS Surface activity was evaluated in pulsating and captive bubble surfactometers and in immature newborn rabbits. RESULTS Preparations containing >or=1% SP-C33 achieve minimum surface tension <5 mN/m indicating good biophysical activity, and increase tidal volumes in premature rabbit fetuses to the same level as a modified natural surfactant preparation does. Alveolar patency at end expiration, as evaluated by measurement of lung gas volumes, histological assessment of alveolar expansion and determination of alveolar volume density, was lower in the animals treated with synthetic surfactant than in those receiving modified natural surfactant. CONCLUSIONS These data suggest that SP-C33 is similarly efficient as the native peptide in improving surface properties of phospholipids mixtures and in increasing lung compliance in surfactant-deficient states, but that other components are needed to maintain alveolar stability at low airway pressures.
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Affiliation(s)
- Andreas Almlén
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
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11
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Johansson H, Nordling K, Weaver TE, Johansson J. The Brichos Domain-containing C-terminal Part of Pro-surfactant Protein C Binds to an Unfolded Poly-Val Transmembrane Segment. J Biol Chem 2006; 281:21032-21039. [PMID: 16709565 DOI: 10.1074/jbc.m603001200] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Native lung surfactant protein C (SP-C) is a 4.2-kDa acylpeptide that associates with alveolar surfactant phospholipids via a transmembrane alpha-helix. This helix contains mainly Val, although poly-Val is inefficient in helix formation, and helical SP-C can spontaneously convert to beta-sheet aggregates and amyloid-like fibrils. SP-C is cleaved out from a 21-kDa integral membrane protein, proSP-C, in the alveolar type II cell. Recently several mutations localized in the endoplasmic reticulum-lumenal (C-terminal) part of proSP-C (CTproSP-C) have been associated with intracellular accumulation of toxic forms of proSP-C, low levels of mature SP-C, and development of interstitial lung disease. CTproSP-C contains a approximately 100-residue Brichos domain of unknown function that is also found in other membrane proteins associated with amyloid formation, dementia, and cancer. Here we find that recombinant CTproSP-C binds lipid-associated SP-C, which is in beta-strand conformation, and that this interaction results in an increased helical content. In contrast, CTproSP-C does not bind alpha-helical SP-C. Recombinant CTproSP-C(L188Q), a mutation associated with interstitial lung disease, shows secondary and quaternary structures similar to those of wild type CTproSP-C but is unable to bind lipid-associated beta-strand SP-C. Transfection of CTproSP-C into HEK293 cells that express proSP-C(L188Q) increases the amount of proSP-C protein, whereas no effect is seen on cells expressing wild type proSP-C. These findings suggest that CTproSP-C binds nonhelical SP-C and thereby prevents beta-sheet aggregation and that mutations in CTproSP-C can interfere with this function.
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Affiliation(s)
- Hanna Johansson
- Department of Molecular Biosciences, Swedish University of Agricultural Sciences, The Biomedical Centre, S-751 23 Uppsala, Sweden
| | - Kerstin Nordling
- Department of Molecular Biosciences, Swedish University of Agricultural Sciences, The Biomedical Centre, S-751 23 Uppsala, Sweden
| | - Timothy E Weaver
- Division of Pulmonary Biology, Cincinnati Children's Research Foundation, Cincinnati, Ohio 45229-3039
| | - Jan Johansson
- Department of Molecular Biosciences, Swedish University of Agricultural Sciences, The Biomedical Centre, S-751 23 Uppsala, Sweden.
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12
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Drochioiu G, Damoc N, Przybylski M. Novel UV assay for protein determination and the characterization of copper–protein complexes by mass spectrometry. Talanta 2006; 69:556-64. [DOI: 10.1016/j.talanta.2005.10.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 10/04/2005] [Accepted: 10/25/2005] [Indexed: 11/25/2022]
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13
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Li J, Liepinsh E, Almlén A, Thyberg J, Curstedt T, Jörnvall H, Johansson J. Structure and influence on stability and activity of the N-terminal propeptide part of lung surfactant protein C. FEBS J 2006; 273:926-35. [PMID: 16478467 DOI: 10.1111/j.1742-4658.2006.05124.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mature lung surfactant protein C (SP-C) corresponds to residues 24-58 of the 21 kDa proSP-C. A late processing intermediate, SP-Ci, corresponding to residues 12-58 of proSP-C, lacks the surface activity of SP-C, and the SP-Ci alpha-helical structure does not unfold in contrast to the metastable nature of the SP-C helix. The NMR structure of an analogue of SP-Ci, SP-Ci(1-31), with two palmitoylCys replaced by Phe and four Val replaced by Leu, in dodecylphosphocholine micelles and in ethanol shows that its alpha-helix vs. that of SP-C is extended N-terminally. The Arg-Phe part in SP-Ci that is cleaved to generate SP-C is localized in a turn structure, which is followed by a short segment in extended conformation. Circular dichroism spectroscopy of SP-Ci(1-31) in microsomal or surfactant lipids shows a mixture of helical and extended conformation at pH 6, and a shift to more unordered structure at pH 5. Replacement of the N-terminal hexapeptide segment SPPDYS (known to constitute a signal in intracellular targeting) of SP-Ci with AAAAAA results in a peptide that is mainly unstructured, independent of pH, in microsomal and surfactant lipids. Addition of a synthetic dodecapeptide, corresponding to the propeptide part of SP-Ci, to mature SP-C results in slower aggregation kinetics and altered amyloid fibril formation, and reduces the surface activity of phospholipid-bound SP-C. These data suggest that the propeptide part of SP-Ci prevents unfolding by locking the N-terminal part of the helix, and that acidic pH results in structural disordering of the region that is proteolytically cleaved to generate SP-C.
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Affiliation(s)
- Jing Li
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
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14
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Danlois F, Zaltash S, Johansson J, Robertson B, Haagsman HP, Rollin F, Ruysschaert JM, Vandenbussche G. Pulmonary surfactant from healthy Belgian White and Blue and Holstein Friesian calves: biochemical and biophysical comparison. Vet J 2003; 165:65-72. [PMID: 12618072 DOI: 10.1016/s1090-0233(02)0092-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The biochemical composition and biophysical behaviour of pulmonary surfactant samples isolated from healthy Belgian White and Blue (BWB) and Holstein Friesian (HF) calves have been investigated and compared. Interesting differences in composition have been demonstrated. In particular, a higher level of total hydrophobic surfactant-associated proteins (SP) (due to higher levels of SP-B and SP-C) is reported in HF calves compared to BWB calves. Higher levels of phosphatidylcholine (PC) and especially the disaturated form of PC were also found in HF as compared to BWB calves. No immediate effect on the surface tension properties evaluated by the pulsating bubble surfactometer was found between the surfactant samples of the two breeds under physiological conditions. However, since a high content of disaturated PC and the presence of the SP-B and SP-C are thought to be essential for the surface activity, we propose that the reported modifications could contribute to the apparently lower resistance of the BWB calves to respiratory troubles in comparison with HF calves.
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Affiliation(s)
- F Danlois
- Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, University of Liège, 20 Boulevard de Colonster, B42, B 4000 Liège, Belgium
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15
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Zaltash S, Griffiths WJ, Beck D, Duan CX, Weaver TE, Johansson J. Membrane activity of (Cys48Ser) lung surfactant protein B increases with dimerisation. Biol Chem 2001; 382:933-9. [PMID: 11501758 DOI: 10.1515/bc.2001.116] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
One of the possible functions of lung surfactant protein B (SP-B), an hydrophobic membrane-associated saposin-like protein, is to reduce the alveolar surface tension by promoting insertion of phospholipids into the air/liquid interface of the lung. SP-B is a covalent homodimer; Cys48 of two polypeptides form an intermolecular disulphide bond. In order to test whether dimerisation of SP-B is important for surfactant function, transgenic mice which express (Cys48Ser) human SP-B in a mouse SP-B null background were generated. In previous studies (Cys48Ser)SP-B showed a concentration-dependent in vitro activity, suggesting that it may form non-covalent dimers. Here (Cys48Ser)SP-B isolated from bronchoalveolar lavage of transgenic mice was studied at different concentrations by circular dichroism (CD) spectroscopy, pulsating bubble surfactometry, mass spectrometry and reversed-phase HPLC. The results indicate that (Cys48Ser)SP-B, both in a phospholipid environment and in organic solvents, is largely monomeric and exhibits low activity at concentrations lower than 1 -2 microM, while at higher concentrations it forms non-covalent dimers, which are nearly functionally equivalent to native SP-B in vitro. Furthermore, electrospray mass spectrometry showed that more dimers were found relative to the monomer when the polarity of the solvent was decreased, and when the concentration of SP-B increased. (Cys48Ser)SP-B also eluted earlier than native SP-B in reversed-phase HPLC. Taken together, these results indicate that a polar surface is buried upon dimerisation, thereby promoting formation of interchain ion pairs between Glu51-Arg52' and Glu51'-Arg52.
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Affiliation(s)
- S Zaltash
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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16
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Stark M, Danielsson O, Griffiths WJ, Jörnvall H, Johansson J. Peptide repertoire of human cerebrospinal fluid: novel proteolytic fragments of neuroendocrine proteins. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 754:357-67. [PMID: 11339279 DOI: 10.1016/s0378-4347(00)00628-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Polypeptides in human cerebrospinal fluid (CSF), isolated by phase separation in chloroform-methanol-water and reversed-phase HPLC, were characterised by sequence analysis and mass spectrometry. This identified the presence of peptide fragments of testican, neuroendocrine specific protein VGF, neuroendocrine protein 7B2, chromogranin B/secretogranin I, chromogranin A, osteopontin, IGF-II E-peptide and proenkephalin. The majority of these fragments were generated by proteolysis at dibasic sites, suggesting that they are derived by activities related to prohormone convertase(s). Several of the fragments have previously not been detected, and their functions in CSF or elsewhere are unknown. A characteristic feature of all these fragments is a very high content of acidic residues, in particular glutamic acid. In addition to the fragments of neuroendocrine proteins, endothelin-binding receptor-like protein 2, ribonuclease 1, IGF-binding protein 6, albumin, alpha1-acid glycoprotein 1, prostaglandin-H2 D-isomerase, apolipoprotein A1, transthyretin, beta2-microglobulin, ubiquitin, fibrinopeptide A, and C4A anaphylatoxin were found.
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Affiliation(s)
- M Stark
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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17
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Palmblad M, Gustafsson M, Curstedt T, Johansson J, Schürch S. Surface activity and film formation from the surface associated material of artificial surfactant preparations. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1510:106-17. [PMID: 11342151 DOI: 10.1016/s0005-2736(00)00339-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Surfactant proteins B and C (SP-B and SP-C) are present in natural derived surfactant preparations used for treatment of respiratory distress syndrome. Herein the surface activity of an SP-C analogue (SP-C(LKS)), a hybrid peptide between SP-C and bacteriorhodopsin (SP-C/BR) and a model peptide (KL(4)) was studied with a captive bubble surfactometer (CBS). The peptides were mixed with either 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)/phosphatidylglycerol (PG) (7:3, by weight) or DPPC/PG/palmitic acid (68:22:9, by weight) at a concentration of 1 mg/ml in HEPES buffer, pH 6.9 and a polypeptide/lipid weight ratio of 0.02--0.03. In some lipid/peptide preparations also 2% of SP-B was included. Adsorption, monitored as surface tension vs. time for 10 min after bubble formation did not show discernible differences for the whole set of preparations. Equilibrium surface tensions of approximately 25 mN/m were reached after 5--10 min for all preparations, although those with SP-C/BR appeared not to reach end point of adsorption within 10 min. Area compression needed to reach minimum surface tension of 0.5--2.0 mN/m was least for the KL(4) preparation, about 13% in the first cycle. 3% SP-C(LKS) in DPPC:PG (7:3, by weight) reached minimum surface tension upon 27% compression in the first cycle. If DPPC:PG:PA (68:22:9, by weight) was used instead only 16% area compression was needed and 14% if also 2% SP-B was included. 3% SP-C(LKS) in DPPC:PG (7:3, by weight)+2% SP-B needed 34% compression to reach minimum surface tension. The replenishment of material from a surface associated surfactant reservoir was estimated with subphase depletion experiments. With the 2% KL(4) preparation incorporation of excess material took place at a surface tension of 25--35 mN/m during stepwise bubble expansion and excess material equivalent to 4.3 monolayers was found. When 2% SP-B was added to 3% SP-C(LKS) in DPPC:PG (7:3, by weight) the number of excess monolayers increased from 1.5 to 3.6 and the incorporation took place at 30--40 mN/m. When SP-B was added to 3% SP-C(LKS) in DPPC:PG:PA (68:22:9, by weight) the number of excess monolayers increased from 0.5 to 3.4 and incorporation took place at 40--50 mN/m. With 2% SP-C/BR incorporation took place at 40--45 mN/m, frequent instability clicks were observed and excess material of approximately 1.1 monolayer was estimated.
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Affiliation(s)
- M Palmblad
- Department of Clinical Chemistry, Karolinska Hospital, Stockholm, Sweden.
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18
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Johansson J, Stark M, Gustafsson M, Wang Y, Zaltash S. Lipopeptide preparation and analysis. EXS 2000; 88:187-98. [PMID: 10803379 DOI: 10.1007/978-3-0348-8458-7_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Lipophilic peptides and proteins present specific problems during preparation and analysis which require the use of modified methodology. This chapter discusses some of the methods that have been employed in the isolation and structural studies of the pulmonary surfactant-associated proteins B and C (SP-B and SP-C), other proteins with lipid-like physicochemical properties, and the SP-B precursor. In particular, methods for separation and analysis of peptide/lipid mixtures, high-resolution separation of lipopeptides, analysis of fatty acylated peptides, and secondary and tertiary structure analysis of lipopeptides are discussed.
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Affiliation(s)
- J Johansson
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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19
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Zahou E, Jörnvall H, Bergman T. Amino acid analysis by capillary electrophoresis after phenylthiocarbamylation. Anal Biochem 2000; 281:115-22. [PMID: 10847618 DOI: 10.1006/abio.2000.4549] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Capillary electrophoresis using SDS in phosphate buffer provides high resolution and short separation time for peptide and protein hydrolysate amino acids after derivatization with phenylisothiocyanate. The phenylthiocarbamyl derivatives are quantified in the picomole and femtomole range at signal-to-noise ratios better than 3:1 (for 50 fmol) and with a linearity correlation coefficient averaging 0.9938. The migration time and peak area variabilities were on average 1.1 and 2.7%, respectively. Complete separation of all the 18 amino acids normally found in polypeptide hydrolysates is achieved in less than 30 min using 75-microm capillaries while 50-microm capillaries require less than 15 min. Analysis of peptide and protein hydrolysates in the range 10-600 residues revealed excellent agreement with the known compositions at sensitivities better by large factors than the corresponding HPLC methodology (about 20-fold) and conventional ninhydrin-based analysis (about 1000-fold).
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Affiliation(s)
- E Zahou
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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20
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Beck DC, Ikegami M, Na CL, Zaltash S, Johansson J, Whitsett JA, Weaver TE. The role of homodimers in surfactant protein B function in vivo. J Biol Chem 2000; 275:3365-70. [PMID: 10652327 DOI: 10.1074/jbc.275.5.3365] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Surfactant protein B (SP-B) is detected in the airways as a sulfhydryl-dependent dimer (M(r) approximately 16,000). To test the hypothesis that formation of homodimers is critical for SP-B function, the cysteine residue reported to be involved in SP-B dimerization was mutated to serine (Cys(248) --> Ser) and the mutated protein was targeted to the distal respiratory epithelium of transgenic mice. Transgenic lines which demonstrated appropriate processing, sorting, and secretion of human SP-B monomer were crossed with SP-B +/- mice to achieve expression of human monomer in the absence of endogenous SP-B dimer (hSP-B(mon), mSP-B-/-). In two of three transgenic lines, hSP-B(mon), mSP-B-/- mice had normal lung structure, complete processing of SP-C proprotein, well formed lamellar bodies, and normal longevity. Pulmonary function studies revealed an altered hysteresis curve for hSP-B(mon), mSP-B-/- mice relative to wild type mice. Large aggregate surfactant fractions from hSP-B(mon), mSP-B-/- mice resulted in higher minimum surface tension in vitro compared with surfactant from wild type mice. Surfactant lipids supplemented with 2% hSP-B monomer resulted in slower adsorption and higher surface tension than surfactant with 2% hSP-B dimer. Taken together, these data indicate a role for SP-B dimer in surface tension reduction in the alveolus.
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Affiliation(s)
- D C Beck
- Division of Pulmonary Biology, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA
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21
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Wang Y, Johansson J, Griffiths WJ. Characterisation of variant forms of prophenin: mechanistic aspects of the fragmentation of proline-rich peptides. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2000; 14:2182-2202. [PMID: 11114029 DOI: 10.1002/1097-0231(20001215)14:23<2182::aid-rcm151>3.0.co;2-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Prophenin 1 (PF-1) is a 79-residue polypeptide originally isolated from porcine leukocytes. Its amino acid sequence has been determined by a combination of mass spectrometry and Edman degradation (Harwig SSL. et al. FEBS Lett. 1995; 362: 65). Prophenin (PF) and variants thereof are also found in organic extracts of porcine pulmonary tissue (Wang Y. et al. FEBS Lett. 1999; 460: 257). In the present study we have characterised the variant forms of PF found in these extracts using nano-electrospray (nano-ES) high resolution and tandem mass spectrometry. The major forms of PF found in these extracts by nano-ES mass spectrometry are the 80-residue polypeptides prophenin-2-Pyr (PF-2-Pyr) and prophenin-2-Gln (PF-2-Gln). Prophenin-2-Pyr is refractory to Edman degradation due to the presence of an N-terminal pyroglutamic residue. In PF-2-Gln the N-terminal residue is glutamine and the C-terminus is amidated. In porcine pulmonary extracts PF-1 is present to only a minor extent. Other shorter polypeptides are also found in these extracts including 18- and 17-residue C-terminal fragments of PF. The primary structure of PF is highly unusual in that it shows four almost perfect decamer repeats of FPPPN(V/F)PGPR and, out of the 79/80 residues, 42 are proline and 14 are phenylalanine. Tryptic digestion of PF gives peptides containing the decamer repeat and collision-induced dissociation of these peptides provides an insight into the fragmentation mechanisms of proline-rich peptides. Facile cleavage within the Pro-Pro-Pro sequence of these peptides suggests the involvement of a cyclic peptide in the fragmentation mechanism. Fragmentation mechanisms that account for the formation of fragment ions at other cleavage sites are also discussed.
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Affiliation(s)
- Y Wang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17177 Stockholm, Sweden
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22
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Stark M, Jörnvall H, Johansson J. Isolation and characterization of hydrophobic polypeptides in human bile. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 266:209-14. [PMID: 10542066 DOI: 10.1046/j.1432-1327.1999.00845.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Polypeptides were isolated from human bile by extraction with chloroform/methanol, followed by reversed-phase chromatography in methanol/ethylene chloride and gel filtration in chloroform/methanol. Peptides were characterized by SDS/PAGE, sequence analysis and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry. This identified haemoglobin alpha chain, ATP synthase lipid-binding protein subunit 9, an N-terminal fragment of mac25/insulin-like growth factor-binding protein 7 and an internal fragment of monocyte differentiation antigen CD14, all not described previously in bile. In addition, alpha1-antitrypsin, known in bile from previous work, was also identified. The hydrophobic character of haemoglobin alpha chain is not apparent from its amino acid sequence, but the other polypeptides all have major hydrophobic segments. These results show that several proteins are removed upon organic solvent extraction used for delipidation during the preparation of samples for proteome analysis. Several of the polypeptides found are unexpectedly present in bile, suggesting that specific excretion mechanisms may be involved.
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Affiliation(s)
- M Stark
- Department of Medical Biochemistry, Karolinska Institutet, Stockholm, Sweden. Margareta,
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23
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Wang Y, Griffiths WJ, Curstedt T, Johansson J. Porcine pulmonary surfactant preparations contain the antibacterial peptide prophenin and a C-terminal 18-residue fragment thereof. FEBS Lett 1999; 460:257-62. [PMID: 10544246 DOI: 10.1016/s0014-5793(99)01363-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Surfactant preparations obtained from porcine lungs by extraction with chloroform/methanol followed by chromatography over Lipidex-5000 are used for treatment of respiratory distress syndrome in preterm infants. These preparations contain about 98% phospholipids and 1-2% of the hydrophobic pulmonary surfactant-associated proteins B and C (SP-B and SP-C). Separation of the proteins in the surfactant preparation by reversed-phase high performance liquid chromatography revealed, in addition to SP-B and SP-C, the presence of three peptides derived from the cathelicidin family of antibacterial peptides. The 79-residue proline-rich peptide prophenin (identical to that isolated from leukocytes), an 80-residue prophenin with an N-terminal pyroglutamic acid residue, and a C-terminal 18-residue fragment of prophenin were found in approximate molar ratios of 1:20:5. A synthetic version of the C-terminal 18-residue peptide exhibits salt-dependent antibacterial activity (higher activity in the absence of salt) against the Gram-positive bacterium Bacillus megaterium Bm11 and, to a lesser extent, against Gram-negative Escherichia coli D21 cells. It appears possible that the presence of prophenin peptides may contribute to the antibacterial properties of surfactant preparations.
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Affiliation(s)
- Y Wang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 77, Stockholm, Sweden
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