• 한국자기공명학회논문지
• /
• 제13권1호
• /
• pp.15-26
• /
• 2009

The NMR detection of methyl groups is of keen interest because they provide the long-range distance information required to establish global folds of high molecular weight proteins. Using longitudinal $^1H$ relaxation optimization, we achieve a gain in sensitivity of approximately 1.6-fold in the methyl-TROSY and its NOESY experiments for the 38 kDa protein mitogen activated protein kinase p38 in its fully protonated and $^{13}C$ and $^{15}N$ labeled state.

• 한국자기공명학회논문지
• /
• 제14권2호
• /
• pp.117-126
• /
• 2010

Hsp33 is a molecular chaperone achieving a holdase activity upon response to a dual stress by heat and oxidation. Despite several crystal structures available, the activation process is not clearly understood, because the structure inactive Hsp33 as its reduced, zinc-bound, monomeric form has not been solved yet. Thus, we initiated structural investigation of the reduced Hsp33 monomer by NMR. In this study, to overcome the high molecular weight (33 kDa), the protein was triply isotope-[$^{13}C$, $^{15}N$, $^2H$]-labeled and its inactive, monomeric state was ensured. 2D-[$^1H$, $^{15}N$]-TROSY and a series of triple resonance spectra could be successfully obtained on a high-field (900 MHz) NMR machine with a cryoprobe. However, under all of the different conditions tested, the number of resonances observed was significantly less than that expected from the amino acid sequence. Thus, a possible contribution of dynamic conformational exchange leading to a line broadening is suggested that might be important for activation process of Hsp33.

• 한국자기공명학회논문지
• /
• 제10권2호
• /
• pp.155-162
• /
• 2006

Angiogenin is unique among angiogenic molecules in that it is a member of the pancreatic ribonuclease superfamily and, in fact, is a ribonucleolytic enzyme. Its enzymatic activity is extremely weak compared to that of the digestive RNases but is critical for its capacity to induce neovascularization. In this study, we completed the backbone resonance assignment of bovine angiogenin using triple resonance NMR experiments of $^{15}N\;and/or\;^{13}C$ isotope labeled protein and investigated the chemical shift variation upon binding with inhibitor phosphate ion and determine the phosphate binding site.

• 약학회지
• /
• 제40권4호
• /
• pp.422-427
• /
• 1996

The anti-Ex-A IgG was specifically labeled with stable isotopes, DL-His-2,4-$d_2$, L-Phe-$d_5$, L-Trp-$d_5$, L-Tyr-2,6-$d_2$ and L-[1-$^{13}C$]Trp, by growing hybridoma cell in serum-free medium. By use of NMR spectroscopy with selectively labeled Fab fragment, we applied a paratope mapping on antigen-antibody complex. Assignments of the observed carbonyl carbon resonances have been determined by using $^{13}C$-$^{15}N$ double labeling method in order to assign the Trp resonances. Photo CIDNP was also applied to investigate the antigen-binding site(s) on the surface residues of antibody. We found that Trp 36, which is located at the $V_H$ domain, is an important residue to bind to Ex-A, however, two Tyr on the surface of anti-Ex-A IgG plays no crucial role to bind to antigen. On the basis of these results, we demonstrate that stable isotope-aided NMR strategy can be extended to molecular structural analyses of the complex of an Fab fragment and a protein antigen.

• Bulletin of the Korean Chemical Society
• /
• 제30권11호
• /
• pp.2647-2650
• /
• 2009

Cold shock proteins (Csps) are a subgroup of the cold-induced proteins on reduction of the growth temperature below the physiological temperature. They preferentially bind to single-stranded nucleic acids to translational regulation via RNA chaperoning. Csp plays important role in cold adaptations for the psychrophilic microorganism. Recently, Cold shock protein from psychrophilic bacteria, Colwellia psychrerythraea (CpCsp) has been identified. Three dimensional structures of a number of Csps from various microorganisms have been solved by NMR spectroscopy or X-ray crystallography, but structures of psychrophilic Csps were not studied yet. Therefore, cloning and purification protocols for further structural study of psychrophilic Csp have been optimized in this study. CpCsp was expressed in E. coli with pET-11a vector system and purified by ion exchange, size exclusion, and reverse phase chromatography. Expression and purification of CpCsp in M9 minimal media was carried out and $^{15}N$-labeled proteins with high purity over 90% was obtained. Further study will be carried out to investigate the tertiary structure and dynamics of CpCsp.

• 한국자기공명학회논문지
• /
• 제16권2호
• /
• pp.172-184
• /
• 2012

The prokaryotic molecular chaperone Hsp33 achieves its holdase activity upon response to oxidative stress particularly at elevated temperature. Despite many structural studies of Hsp33, which were conducted mainly by X-ray crystallography, the actual structures of the Hsp33 in solution remains controversial. Thus, we have initiated NMR study of the reduced, inactive Hsp33 monomer and backbone NMR assignments were obtained in the present study. Based on a series of triple resonance spectra measured on a triply isotope-[$^2H/^{13}C/^{15}N$]-labeled protein, sequence-specific assignments of the backbone amide signals observed in the 2D-[$^1H/^{15}N$]TROSY spectrum could be completed up to more than 96%. However, even considering the small portion of non-assigned resonances due to the lack of sequential connectivity, we confirmed that the total number of observed signals was quite smaller than that expected from the number of amino acid residues in Hsp33. Thus, it is postulated that peculiar dynamic properties would be involved in the solution structure of the inactive Hsp33 monomer. We expect that the present assignment data would eventually provide the most fundamental and important data for the progressing studies on the 3-dimensional structure and molecular dynamics of Hsp33, which are critical for understanding its activation process.

• International Neurourology Journal
• /
• 제22권4호
• /
• pp.260-267
• /
• 2018

Purpose: A major question remaining in approaches to tissue engineering and organ replacement is the role of native mobilized native cells in the regeneration process of damaged tissues and organs. The goal of this study was to compare the cell mobilizing effects of the chemokine CXCL12 and cell therapy on the urinary sphincter of nonhuman primates (NHP) with chronic intrinsic urinary sphincter dysfunction. Methods: Either autologous lenti-M-cherry labeled skeletal muscle precursor cells (skMPCs) or CXCL12 were injected directly into the sphincter complex of female NHPs with or without surgery-induced chronic urinary sphincter dysfunction (n=4/treatment condition). All monkeys had partial bone marrow transplantation with autologous lenti-green fluorescent protein (GFP) bone marrow cells prior to treatment. Labeled cells were identified, characterized and quantified using computer-assisted immunohistochemistry 6 months posttreatment. Results: GFP-labeled bone marrow cells (BMCs) were identified in the bone marrow and both BMCs and skMPCs were found in the urinary sphincter at 6-month postinjection. BMCs and skMPCs were present in the striated muscle, smooth muscle, and lamina propria/urothelium of the sphincter tissue. Sphincter injury increased the sphincter content of BMCs when analyzed 6-month postinjection. CXCL12 treatment, but not skMPCs, increased the number of BMCs in all layers of the sphincter complex (P<0.05). CXCL12 only modestly (P=0.15) increased the number of skMPCs in the sphincter complex. Conclusions: This dual labeling methodology now provides us with the tools to measure the relative number of locally injected cells versus bone marrow transplanted cells. The results of this study suggest that CXCL12 promotes mobilization of cells to the sphincter, which may contribute more to sphincter regeneration than injected cells.

• Journal of Microbiology and Biotechnology
• /
• 제16권9호
• /
• pp.1429-1433
• /
• 2006

Application of recombinant protein production and particularly their isotopic enrichment has stimulated development of a range of novel multidimensional heteronuclear NMR techniques. Peptides in most cases are amenable to assignment and structure determination without the need for isotopic labeling. However, there are many cases where the availability of $^{15}N$ and/or $^{13}C$ labeled peptides is useful to study the structure of peptides with more than 30 residues and the interaction between peptides and membrane. CRAMP (Cathelicidin-Related AntiMicrobial Peptide) was identified from a cDNA clone derived from mouse femoral marrow cells as a member of cathelicidin-derived antimicrobial peptides. CRAMP was successfully expressed as a GST-fused form in E. coli and purified using affinity chromatography and reverse-phase chromatography. The yield of the CRAMP was 1.5 mg/l 1. According to CD spectra, CRAMP adopted ${\alpha}$-helical conformation in membrane-mimetic environments. Isotope labeling of CRAMP is expected to make it possible to study the structure and dynamic properties of CRAMP in various membrane systems.

• 한국자기공명학회논문지
• /
• 제26권3호
• /
• pp.34-39
• /
• 2022

The SH3 domain found within a variety of proteins is comprised of generally 60 residues, and participated in protein-protein interactions with proline-rich motifs. Cobll1 was identified as a distinct molecular marker associated with CML progression, and PACSIN2 was discovered a novel Cobll1 binding partner through direct interaction between a SH3 domain of PACSIN2 and three proline-rich motifs of Cobll1. To understand the structural basis of interactions between PACSIN2 and Cobll1, backbone assignments of PACSIN2 SH3 domain were performed. Furthermore, three proline-rich peptides of Cobll1 were titrated to ¹⁵N-labeled PACSIN2 SH3 domain in various ratios. Our chemical shift changes data and conserved SH3 sequence alignment will be helpful to analyze fundamental molecular basis related to the interaction between PACSIN2 and Cobll1.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제39권2호
• /
• pp.63-70
• /
• 2013

Objectives: The purpose of this study was to investigate the wound healing effect of primary cultured oral mucosal keratinocytes (OMKs) and to assess their roles in skin wounds. Materials and Methods: OMK labeled with BromodeoxyUridine were scattered onto $1.5{\times}1.5$ cm skin defects of adult female nude mice (OMK group, n=15). For the control, culture media were placed on the wound (control group, n=15). Mice in both groups were sacrificed at three days (n=5), one week (n=5), and two weeks (n=5), and histomorphometric and immunoblot analyses with keratinocyte growth factor (KGF), interleukin (IL)-6, and IL-$1{\alpha}$ antibody were performed for the biopsied wound specimen. To verify the effect of the cytokine, rhIL-$1{\alpha}$ was applied instead of OMK transplantation, and the OMK and control groups were compared with regard to re-epithelialization. Results: Histomorphometric analyses demonstrated faster re-epithelialization in the graft group than in the control group at the third day, first week, and second week. Newly forming epithelium showed maintenance of the histological character of the skin epithelium. The graft group showed superior expression of KGF, IL-6, and IL-$1{\alpha}$ protein, compared with the control group. Similar faster re-epithelialization was observed after treatment with rhIL-$1{\alpha}$ instead of OMK transplantation. Conclusion: We successfully confirmed that the graft of primary cultured OMKs promoted regeneration of skin defects. The mechanism of accelerated wound healing by primary cultured OMKs was attributed to inducement of cytokine expression as required for re-epithelialization.