Biomedical subjects

M R Larsen

Publications and source records attributed to M R Larsen.

At least 19 recordsLinked to original sources

PubMed2006

Changes in the muscle proteome after compensatory growth in pigs.

Sixteen female pigs (Duroc x Landrace x Large White) were divided into 2 groups, which had either free access to the diet (control group) or were feed-restricted from d 28 to 80 and then had free access to the diet (compensatory growth group). The sensory analysis showed that the pigs exhibiting compensatory growth produced meat with increased tenderness compared with control pigs (P < 0.05). To gain further knowledge of the influence of compensatory growth on meat tenderness, the sarcoplasmic protein fraction of muscle tissue was studied at the time of slaughter and 48 h postmortem using proteome analysis. At slaughter, 7 different proteins were found to be affected by compensatory growth: HSC70, HSP27, enolase 3, glycerol-3-phosphate dehydrogenase, aldehyde dehydrogenase E2, aldehyde dehydrogenase E3, and biphosphoglycerate mutase. The HSC70 and HSP27 both belong to the heat shock family and are known to play a role during muscle development. Hence, they may be affected by compensatory growth and increased protein turnover. Forty-eight hours after slaughter, 8 different proteins were found to be affected by compensatory growth: myosin light chain (MLC) II, MLC III, sulfite oxidase, chloride intracellular channel 1, 14-3-3 protein gamma, elongin B, and phosphohistidine phosphatase 14. The changes observed on MLC II and MLC III could be a consequence of enzymatic cleavage in the neck region of the globular myosin head domain that causes the release of MLC II and MLC III from the actomyosin complex. It has previously been hypothesized that compensatory growth results in an increased postmortem proteolysis; thus it was presumed that the intensity of some protein fragments would be affected by compensatory growth. However, the peptides that were found to be affected at 48 h postmortem were all full-length proteins. The 14-3-3 protein gamma has been proposed to play a role in the contraction of muscle during rigor and may thereby have an effect on meat tenderness. This study reveals some very interesting changes in the muscle proteome affected by compensatory growth, which may be useful in understanding the relationship among compensatory growth, protein turnover, and meat tenderness.

Animal Feed↗

PubMed2003

Protein expression changes in a cell system of beta-cell maturation reflect an acquired sensitivity to IL-1beta.

AIM/HYPOTHESIS: Type 1 diabetes mellitus (T1DM) is caused by specific destruction of the pancreatic beta cells in the islets of Langerhans. Increased sensitivity to cytokines, in particular to interleukin-1beta (IL-1beta) seems to be an acquired trait during beta-cell maturation. In response to cytokines both protective and deleterious mechanisms are induced in beta cells, and when the deleterious prevail, T1DM develops. The aims of this study were to identify perturbation in protein patterns (PiPP) associated with beta-cell maturation, and compare these changes to previous analyses of IL-1beta exposed rat islets. For this purpose, proteome analyses were carried out using a cell-line, which matures from a glucagon-producing pre-beta-cell phenotype (NHI-glu) to an insulin-producing beta-cell phenotype (NHI-ins). We have previously shown that this maturation is accompanied by acquired sensitivity to the toxic effects of IL-1beta. METHODS: 2D-gel electrophoresis was used to separate the proteins and MALDI-MS and database searches were performed to identify the proteins. RESULTS: During beta-cell maturation 135 protein spots out of 2239 detectable changed expression levels. Of these, 74 were down-regulated, 44 up-regulated, 16 were suppressed and 1 was expressed de novo. Using MALDI-MS, positive identification was obtained for 93 out of the 135 protein-spots revealing 97 different proteins. Of these, 22 proteins were in common with changes identified in previous proteome analysis of perturbation in protein pattern in IL-1beta exposed rat islets. Several of the proteins were present in more than one spot suggesting post-translational modification. CONCLUSION/INTERPRETATION: Several proteins and protein modifications were identified that could be critically involved in beta-cell maturation, insulin-gene expression and the acquired IL-1beta sensitivity.

Animals↗

PubMed2003

Intrauterine programming of fetal islet gene expression in rats--effects of maternal protein restriction during gestation revealed by proteome analysis.

AIMS/HYPOTHESIS: Fetal undernutrition can result in intrauterine growth restriction and increased incidence of Type 2 diabetes mellitus. Intrauterine malnutrition in form of an isocaloric low-protein diet given to female rats throughout gestation decreases islet-cell proliferation, islet size and pancreatic insulin content, while increasing the apoptotic rate and sensitivity to nitrogen oxide and interleukin-1beta. Hence, the influence of a low-protein diet on the development of beta-cells and islets could also be of interest for the pathogenesis of Type 1 and Type 2 diabetes mellitus. We hypothesise that the effects of a low-protein diet in utero are caused by intrauterine programming of beta-cell gene expression. METHODS: Pregnant Wistar rats were fed a low-protein diet (8% protein) or a control diet (20% protein) throughout gestation. At day 21.5 of gestation fetal pancreata were removed, digested and cultured for 7 days. Neoformed islets were collected and analysed by proteome analysis comprising 2-dimensional gel electrophoresis and mass spectrometry. RESULTS: A total of 2810 different protein spots were identified, 70 of which were changed due to the low-protein diet. From 45 of the changed protein spots, identification was obtained by mass spectrometry (64% success rate). Proteins induced by the low-protein diet were grouped according to their biological functions, e.g. cell cycle and differentiation, protein synthesis and chaperoning. CONCLUSIONS/INTERPRETATION: Our study offers a possible explanation of the alterations induced by a low-protein diet in islets. It shows that in Wistar rats the intrauterine milieu could program islet gene expression in ways unfavourable for the future of the progeny. This could be important for our understanding of the development of Type 1 and Type 2 diabetes mellitus.

Animals↗

PubMed2001

The brain exocyst complex interacts with RalA in a GTP-dependent manner: identification of a novel mammalian Sec3 gene and a second Sec15 gene.

Ral is a small GTPase involved in critical cellular signaling pathways. The two isoforms, RalA and RalB, are widely distributed in different tissues, with RalA being enriched in brain. The best characterized RalA signaling pathways involve RalBP1 and phospholipase D. To investigate RalA signaling in neuronal cells we searched for RalA-binding proteins in brain. We found at least eight proteins that bound RalA in a GTP-dependent manner. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) identified these as the components of the exocyst complex. The yeast exocyst is a regulator of polarized secretion, docking vesicles to regions of the plasma membrane involved in active exocytosis. We identified the human FLJ10893 protein as the mammalian homologue of the yeast exocyst protein Sec3p. The exocyst complex did not contain the previously identified exocyst component rSec15, but a new homologue of both yeast Sec15p and rSec15, called KIAA0919. Western blots confirmed that two rat exocyst proteins, rSec6 and rSec8, bound active RalA in nerve terminals, as did RalBP1. Phospholipase D bound RalA in a nucleotide-independent manner. This places the RalA signaling system in mammalian nerve terminals, where the exocyst may act as an effector for activated RalA in directing sites of exocytosis.

Amino Acid Sequence↗

PubMed2001

Characterization of differently processed forms of enolase 2 from Saccharomyces cerevisiae by two-dimensional gel electrophoresis and mass spectrometry.

Two-dimensional gel electrophoresis, bioinformatics, and mass spectrometry are key analysis tools in proteome analysis. The further characterization of post-translational modifications in gel-separated proteins relies fully on data obtained by mass spectrometric analysis. In this study, stress-induced changes in protein expression in Saccharomyces serevisiae were investigated. A total of eleven spots on a silver-stained two-dimensional (2-D) gel were identified by matrix-assisted laser desorption/ionization (MALDI) peptide mass mapping to represent C and/or N-terminal processed forms of enolase 2. The processing sites were determined by MALDI peptide mass mapping using a variety of proteolytic enzymes, by optimizing the sample preparation procedure and by specific labeling of all C-termini derived from in-gel digestion using a buffer containing 16O:18O (1:1). Out of eleven processed forms of enolase 2, six were fully characterized and the approximate processing sites identified for the remaining five.

Amino Acid Sequence↗

PubMed2001

Phospho-proteomics: evaluation of the use of enzymatic de-phosphorylation and differential mass spectrometric peptide mass mapping for site specific phosphorylation assignment in proteins separated by gel electrophoresis.

Detection of phosphorylated proteins as well as assignment of the phosphorylated sites in such proteins is a major challenge in proteomics. In the present study we evaluate the use of enzymatic de-phosphorylation in combination with differential peptide mass mapping for identification of phosphorylated peptides in peptide mixtures derived from in-gel digested phospho-proteins. Phospho-peptides could be identified provided that improved sample preparation methods prior to mass spectrometric analysis were used. An attempt to identify the proteins visualized by [32P] autoradiography in a proteomics study and their phosphorylation sites, demonstrated that protein identification was possible whereas reliable identification of the phospho-peptides requires more protein than normally available in our proteomics studies.

Alkaline Phosphatase↗

PubMed2001

Phosphorylation of the Fas associated factor FAF1 by protein kinase CK2 and identification of serines 289 and 291 as the in vitro phosphorylation sites.

We previously identified the human Fas associated factor (FAF1) as one of the interacting partners of protein kinase CK2 beta subunit. Since FAF1 is a phosphoprotein we investigated whether it is a substrate for CK2. Here, we report the full length human FAF1 cDNA sequence, expression of FAF1 in Escherichia coli and purification and characterization of FAF1 as a substrate for CK2. FAF1 as well as an N-terminal 40 kDa degradation product serve as substrates for both the recombinant CK2 holoenzyme (km 100 microM) and the isolated catalytic alpha subunit (km 200 microM). Despite the high k(m) values, we obtained evidence that CK2 is the major cellular kinase responsible for FAF1 phosphorylation, using tissue extracts as kinase sources. By MALDI-MS we identified the two serine residues at positions 289 and 291 as the major in vitro CK2 phosphorylation sites. These data may help us elucidate the functions of FAF1 and the involvement of CK2 mediated phosphorylation in processes such as apoptotic signaling, ubiquitination, nuclear translocation and embryonic development.

Adaptor Proteins, Signal Transducing↗

PubMed2001

Proteome analysis of interleukin-1beta--induced changes in protein expression in rat islets of Langerhans.

The intracellular molecular events involved in the beta-cell death process are complex but poorly understood. Cytokines, e.g., interleukin (IL)-1beta, may play a crucial role in inducing this process. Protein synthesis is necessary for the deleterious effect of IL-1, and induction of both protective and deleterious proteins has been described. To characterize the rather complex pattern of islet protein expression in rat islets in response to IL-1, we have attempted to identify proteins of altered expression level after IL-1 exposure by 2D gel electrophoresis and mass spectrometry. Of 105 significantly changed (i.e., up- or downregulated or de novo-induced) protein spots, we obtained positive protein identification for 60 protein spots. The 60 identifications corresponded to 57 different proteins. Of these, 10 proteins were present in two to four spots, suggesting that posttranslatory modifications had occurred. In addition, 11 spots contained more than one protein. The proteins could be classified according to their function into the following groups: 1) energy transduction; 2) glycolytic pathway; 3) protein synthesis, chaperones, and protein folding; and 4) signal transduction, regulation, differentiation, and apoptosis. In conclusion, valuable information about the molecular mechanisms involved in cytokine-mediated beta-cell destruction was obtained by this approach.

Animals↗

PubMed2000

Stanniocalcin 1 and 2 are secreted as phosphoproteins from human fibrosarcoma cells.

Stanniocalcin 1 (STC1) and stanniocalcin 2 (STC2) are two recently identified mammalian peptide hormones. STC1 plays a role in calcium and phosphate homoeostasis, while the role of STC2 is unknown. We examined a human fibrosarcoma cell line, HT1080, that has high steady-state STC1 and STC2 mRNA levels, to determine whether these proteins are secreted. Following incubation of HT1080 cells with (32)P, labelled STC1 and STC2 were found to be secreted into the medium. STC1 was phosphorylated in vitro by protein kinase C (PKC). In vitro and in vivo phosphorylation both occurred exclusively on serine and the phosphopeptide maps were similar, suggesting that PKC might be the in vivo kinase. STC2 was phosphorylated in vitro by casein kinase II (CK2), in vitro and in vivo phosphorylation were exclusively on serine and the phosphopeptide maps were indistinguishable. Phosphorylation of STC2 in intact cells resulted from the action of an ecto-protein kinase, since exogenous STC2 was phosphorylated by HT1080 cells and no phosphorylated STC2 was detectable inside the cells. The ectokinase activity was abolished by heparin and GTP could substitute for ATP as the phosphate donor, indicative of an ecto-CK2-like activity. The in vitro CK2 phosphorylation site was shown by matrix-assisted laser-desorption ionization-time-of-flight MS to be a single serine located between Ser-285 and Ser-298 in the C-terminal region of STC2. This is the first report of the secretion of STC1 or STC2 from mammalian cells. We conclude that these human fibrosarcoma cells express both STC1 and STC2 as secreted phosphoproteins in vivo, with STC2 being phosphorylated by an ecto-CK2-like enzyme.

Blotting, Western↗

PubMed2000

Heterogeneous nuclear ribonucleoproteins C1/C2 identified as autoantigens by biochemical and mass spectrometric methods.

The antigenic specificity of an unusual antinuclear antibody pattern in three patient sera was identified after separating HeLa-cell nuclear extracts by two-dimensional (2D) gel electrophoresis and localizing the antigens by immunoblotting with patient serum. Protein spots were excised from the 2D gel and their contents were analyzed by matrix-assisted laser desorption-ionization (MALDI) or nanoelectrospray ionization time-of-flight (TOF) tandem mass spectrometry (MS) after in-gel digestion with trypsin. A database search identified the proteins as the C1 and C2 heterogeneous nuclear ribonucleoproteins. The clinical spectrum of patients with these autoantibodies includes arthritis, psoriasis, myositis, and scleroderma. None of 59 patients with rheumatoid arthritis, 19 with polymyositis, 33 with scleroderma, and 10 with psoriatic arthritis had similar antibodies. High-resolution protein-separation methods and mass-spectrometric peptide mapping in combination with database searches are powerful tools in the identification of novel autoantigen specificities.

Adult↗

PubMed2000

Phosphorylation of dynamin I on Ser-795 by protein kinase C blocks its association with phospholipids.

Dynamin I is phosphorylated in nerve terminals exclusively in the cytosolic compartment and in vitro by protein kinase C (PKC). Dephosphorylation is required for synaptic vesicle retrieval, suggesting that its phosphorylation affects its subcellular localization. An in vitro phospholipid binding assay was established that prevents lipid vesiculation and dynamin lipid insertion into the lipid. Dynamin I bound the phospholipid in a concentration-dependent and saturable manner, with an apparent affinity of 230 +/- 51 nM. Optimal binding occurred with mixtures of phosphatidylserine and phosphatidylcholine of 1:3 with little binding to phosphatidylcholine or phosphatidylserine alone. Phospholipid binding was abolished after dynamin I phosphorylation by PKC and was restored after dephosphorylation by calcineurin. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry revealed the phosphorylation site in PKCalpha-phosphorylated dynamin I as a single site at Ser-795, located near a binding site for the SH3 domain of p85, the regulatory subunit of phosphatidylinositol 3-kinase. However, phosphorylation had no effect on dynamin binding to a bacterially expressed p85-SH3 domain. Thus, phosphorylation of dynamin I on Ser-795 prevents its association with phospholipid, providing a basis for the cytosolic localization of the minor pool of phospho-dynamin I that mediates synaptic vesicle retrieval in nerve terminals.

Adenine Nucleotides↗

PubMed2000

Complementing genomics with proteomics: the membrane subproteome of Pseudomonas aeruginosa PAO1.

With the completion of many genome projects, a shift is now occurring from the acquisition of gene sequence to understanding the role and context of gene products within the genome. The opportunistic pathogen Pseudomonas aeruginosa is one organism for which a genome sequence is now available, including the annotation of open reading frames (ORFs). However, approximately one third of the ORFs are as yet undefined in function. Proteomics can complement genomics, by characterising gene products and their response to a variety of biological and environmental influences. In this study we have established the first two-dimensional gel electrophoresis reference map of proteins from the membrane fraction of P. aeruginosa strain PA01. A total of 189 proteins have been identified and correlated with 104 genes from the P. aeruginosa genome. Annotated membrane proteins could be grouped into three distinct categories: (i) those with functions previously characterised in P. aeruginosa (38%); (ii) those with significant sequence similarity to proteins with assigned function or hypothetical proteins in other organisms (46%); and (iii) those with unknown function (16%). Transmembrane prediction algorithms showed that each identified protein sequence contained at least one membrane-spanning region. Furthermore, the current methodology used to isolate the membrane fraction was shown to be highly specific since no contaminating cytosolic proteins were characterised. Preliminary analysis showed that at least 15 gel spots may be glycosylated in vivo, including three proteins that have not previously been functionally characterised. The reference map of membrane proteins from this organism is now the basis for determining surface molecules associated with antibiotic resistance and efflux, cell-cell signalling and pathogen-host interactions in a variety of P. aeruginosa strains.

Bacterial Proteins↗

PubMed2000

Cytokine- or chemically derived nitric oxide alters the expression of proteins detected by two-dimensional gel electrophoresis in neonatal rat islets of Langerhans.

Interleukin-1beta (IL-1beta) treatment of neonatal rat islets for 24 h induces changes in the expression of 105 of 2,200 proteins, as determined previously by two-dimensional (2D) gel electrophoresis. Nitric oxide (NO) has been implicated as one of the mediators of IL-1beta effects in insulin-containing cell lines and rat islets. The aims of this study were 1) to determine the involvement of NO in IL-1beta-induced alterations in protein expression and 2) to investigate the effects of chemically generated NO on protein expression by 2D gel electrophoresis of neonatal rat islet samples. IL-1beta-induced NO production was prevented by incubation of islets in arginine-free medium supplemented with the arginine analog NG-nitro-L-arginine. [35S]methionine-labeled islet proteins were separated using 2D gel electrophoresis and analyzed using the BioImage computer program. Analysis revealed that the expression levels of 23 protein spots of the 105 protein spots, altered by prior treatment with IL-1beta (60 U/ml) alone, were significantly affected (P < 0.01 [n = 4] and P < 0.05 [n = 19]) when NO production was prevented. The effects of chemically generated NO were investigated by exposing islets to the NO donor GSNO (100 micromol/l) for 24 h before labeling with [35S]methionine and 2D gel electrophoresis. Computer-based analysis identified alterations in the expression of 19 of a total of 1,600 detectable proteins in GSNO-treated islets (P < 0.01). We conclude 1) that the expression of up to 42 proteins is altered by cytokine-induced or chemically generated NO in the precise experimental conditions chosen and 2) that the majority of proteins altered by prior treatment with IL-1beta may be the result of NO-independent IL-1beta-mediated regulation of gene expression. This study demonstrates that the combination of 2D gel electrophoresis and mass spectrometry is a powerful tool in the identification of beta-cell proteins involved in the response to toxic mediators.

Animals↗

PubMed1999

Two-dimensional gel analysis of human endometrial proteins: characterization of proteins with increased expression in hyperplasia and adenocarcinoma.

In the search for new markers of human endometrial hyperplasia and adenocarcinoma the method of quantitative two-dimensional gel electrophoresis was applied to study the protein expression profiles of metabolically [(35)S]-methionine-labelled proteins of endometrial explants. Approximately 1700 protein spots were resolved by the two-dimensional gel electrophoresis, and the expression pattern of each of these proteins was assessed for increased expression during hyperplasia or adenocarcinoma. In total, six protein spots showed increased expression in hyperplasia, 19 in carcinoma, and eight in both hyperplasia and carcinoma. Twelve of these 33 differentially expressed proteins were identified by peptide mass mapping combined with sequence database searching. Among the identified proteins were proteins involved in cellular transport and chaperoning, i.e. heat shock protein 27 kDa protein, heat shock 70 kDa protein, heat shock cognate 71 kDa protein, and serotransferrin. Other identified proteins were: regulatory chain protein of cAMP-dependent protein kinase, prohibitin, and heterogeneous nuclear ribonucleoprotein A2/B1. Finally we identified proteins associated with the cytoskeleton, vimentin and tropomyosin isoform 3, and the glycolytic pathway, alpha enolase, and phosphoglycerate kinase. The remaining unidentified proteins were either not contained in the database and must be assumed to be novel proteins, or were present in too low amounts to allow characterization.

Adenocarcinoma↗

PubMed1998

Mass spectrometric identification and microcharacterization of proteins from electrophoretic gels: strategies and applications.

The entire genomic DNA sequences of a number of prokaryotic and eukaryotic species are now available and many more, including the human genome, will be completed in the near future. The state-of-life of a cell at any given time, however, is defined by its protein composition, i.e., its proteome. Gel electrophoresis, mass spectrometry, and bioinformatics will be important tools for protein and proteome analysis in the post-genome era. Protein identification from electrophoretic gels by mass spectrometric peptide mapping or peptide sequencing combined with sequence database searching is established and has been applied to numerous biological systems. We describe current strategies and selected applications in molecular and cell biology. The next challenges are detailed structure/function analyses, which include studying the molecular composition of multiprotein complexes and characterization of secondary modifications of proteins. The advantages and limitations of a number of mass spectrometry-based strategies designed for microcharacterization of low amounts of protein from electrophoretic gels are discussed and illustrated by examples.

Amino Acid Sequence↗

PubMed1998

Correlation of acidic and basic carrier ampholyte and immobilized pH gradient two-dimensional gel electrophoresis patterns based on mass spectrometric protein identification.

Separation of proteins on either carrier ampholyte-based or immobilized pH gradient-based two-dimensional (2-D) gels gives rise to electrophoretic patterns that are difficult to compare visually. In this paper we have used matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to determine the identities of 335 protein spots in these two 2-D gel systems, including a substantial number of basic proteins which had never been identified before. Proteins that were identified in both gel systems allowed us to cross-reference the gel patterns. Vector analysis of these cross-references demonstrated that there is no obvious pattern by which the mobility of a protein in one gel system can be used to predict its mobility in the other. Thus, as laboratories adopt the immobilized pH gradient-based 2-D gel systems, the only reliable means of translating the data gained with the carrier ampholyte-based gel system is to positively identify the proteins in both 2-D systems.

Ampholyte Mixtures↗

PubMed1997

Proteome analysis of Saccharomyces cerevisiae: a methodological outline.

Proteome analysis offers a unique means of identifying important proteins, characterizing their modifications and beginning to describe their function. This is achieved through the combination of two technologies: protein separation and selection by two-dimensional gel electrophoresis, and protein identification and characterization by mass spectrometry. This methodological outline sketches the strengths and weaknesses of the two central technologies used, and provides both practical tips and the theoretical background for their utilization. One application of these technologies is illustrated by the characterization of genes, revealed by sequencing, but which have no--or only weak homology--to any other known genes. Other applications, for example the identification of protein markers for particular human diseases, are only referred to. The aim of the article is thus to provide the basis for a sound understanding of the full potential and limitations of proteome analysis.

Databases, Factual↗

PubMed1996

Characterization of purified recombinant Bet v 1 with authentic N-terminus, cloned in fusion with maltose-binding protein.

A gene encoding the pollen major allergen Bet v 1 from Betula verrucosa (White Birch) has been cloned and expressed in Escherichia coli as a fusion with maltose-binding protein and a Factor Xa proteolytic cleavage site. A generally applicable cloning strategy based on polymerase chain reaction was designed to position the Factor Xa proteolytic site so that the authentic amino terminus of Bet v 1 was generated after cleavage. Fusion protein was isolated by amylose affinity chromatography and enzymatically cleaved by incubation with Factor Xa. Recombinant Bet v 1 was isolated by gel filtration and gave rise to a single band with apparent molecular weight of 17 kDa when analyzed by SDS-polyacrylamide gel electrophoresis. N-terminal sequencing of the first 20 amino acids showed complete agreement with the deduced Bet v 1 DNA sequence. Mass spectrometry showed that recombinant Bet v 1 has a molecular mass of 17,440 +/- 2 Da; 86% of the recombinant Bet v 1 amino acid sequence could be verified by digestion with Lys-C and mass spectrometric peptide mapping. The yield of purified recombinant Bet v 1 was 10 mg per liter E. coli cell culture. Two-dimensional gel electrophoresis of purified recombinant protein gave rise to one major protein spot and one or two minor spots focusing at slightly different pHs. The immunochemical properties of recombinant protein were indistinguishable from those of naturally occurring Bet v 1 when compared using a panel of murine monoclonal antibodies and serum IgE from birch pollen allergic patients. Furthermore, recombinant Bet v 1 elicited T-cell proliferation comparable to that of natural Bet v 1. Thus, the methods used for bacterial expression and protein purification result in relatively high yields of folded recombinant Bet v 1 with correct N-terminal sequence and molecular mass. Furthermore, the B- and T-cell epitope structures of recombinant Bet v 1 closely resemble those of the natural protein from pollen.

ATP-Binding Cassette Transporters↗