As for all of the GO concentrations, the characteristic peaks for assembled GO were similar, and the relative intensity of D band to G band was about 0.95. When GO sheets on the electrodes were reduced with hydrazine and pyrrole, the peaks of D and G bands of rGO blueshifted a little. Meanwhile, the relative intensity of D band increased substantially for Hy-rGO, i.e., an increase of D/G intensity ratio of rGO (about 1.40) compared to that of the GO could be observed. These changes

suggested an increase in the average size of the sp 2 domains upon reduction of GO, which agreed well with the Raman spectrum of the GO reduced by hydrazine that was reported by Stankovich et al. [42], indicating that reduction did happen. buy GSK1838705A However, when GO was reduced by pyrrole, the situation was totally different. The peaks of D and G bands were wider than those of MI-503 in vitro Hy-rGO, and the D/G intensity ratio decreased to about 0.90. This might be due to the polypyrrole (PPy) molecules adsorbed on the surfaces of rGO sheets. As we know, GO has long been

recognized as having strong oxidizing properties, and it can serve as an oxidizing agent [43, 44] for oxidative polymerization of pyrrole during the reduction process [45]. Since PPy molecule was a conducting polymer with ordered conjugated structures, PPy molecules on the surfaces of rGO sheets would decrease the D band (disordered structure) and meanwhile increase the G band (ordered structure) of rGO sheets. G protein-coupled receptor kinase As a result, lower relative D band intensities were obtained. Figure 6 Raman spectra of GO, Hy-rGO, and Py-rGO after assembly of the electrodes with GO concentrations. (a) 1 mg/mL, (b) 0.5 mg/mL, and (c) 0.25 mg/mL with the excitation wavelength at 514 nm. In addition, the sizes of the crystalline domains within the rGO flakes could be estimated from the following equation [46]: (1) where L a is the size of the crystalline domains within CRG, λlaser is the excitation wavelength of the Raman spectra, and is the D/G intensity ratio. A D/G ratio of 1.4 and 0.9 with the excitation

wavelength at 514 nm for selleck Hy-rGO and Py-rGO respectively in our work (Figure  3c) suggested that crystalline domains with the size of ca. 12 and ca. 18.7 nm respectively had been formed in within the resultant Hy-rGO and Py-rGO flakes. Evaluation of sensing devices based on assembled rGO sheets The resistances of the resultant sensing devices were measured by applying 50 mV of voltage and the results were shown in Figure  7a, b. The current versus voltage (I-V) curves of the sensing devices based on Hy-rGO and Py-rGO (as shown in Figure  7a, b), which were fabricated with GO assembly concentration at 1, 0.5, and 0.25 mg/mL, exhibited linear ohmic behaviors, suggesting that perfect circuits of the sensing devices had been achieved.

It has been reported that BMP4 is overexpressed in melanoma cell line and lung cancer. BMP4 plays an important role in bone metastasis of SC79 prostate cancer [16], and BMP4 overexpression inhibits proliferation and induces apoptosis in many cancer cell line [15, 17]. This study also showed that BMP-4 expression was lower in primary tumors. Bone metastasis of lung cancer is a dynamic process involving bone resorption resulted from tumor cell-induced osteolysis and bone formation due to osteoblasts. This study didn’t show PTHrP and IGF-1R overexpression in NSCLC tissue related NSCLC bone metastasis. PTHrP is required

for colony of bone metastasis of cancer cells. It is a cytokine produced by the metastatic cancer cells [18]. But Henderson [19] had PF-6463922 order demonstrated that bone metastases that do not express PTHrP in primary breast cancer begin to do so when they reach bone. The bone microenvironment seems to provide what is needed for the breast cancer cells to produce PTHrP, even if they could not produce it before they got there. This study demonstrated that PTHrP was expressed only in 66.67% of the primary tumors. Breast cancer overexpress IGF-1R through promoting proliferation and reducing apoptosis to increase bone metastasis [20], the effects of IGF-1R have been confirmed in bone metastasis of prostate cancer [21] but the role of IGF-1R overexpress in NSCLC bone metastasis is

not clear, it still needs to be further investigated. Multivariate Logistic regression MK-4827 mw clonidine has successfully established a model for predicting the risk of bone metastasis

in resected Stage III NSCLC: logit (P) = − 2.538 +2.808 CXCR4 +1.629 BSP +0.846 OPG-2.939BMP4. The area under the ROC curve was 81.5%. When P = 0.408, the sensitivity was up to 71%, specificity 70%. The model has successfully validated in 40 patients with resected stage III NSCLC from 2007 to 2009 whole cohort in clinic trial, who were followed up for 3 years. The model showed a sensitivity of 85.7% and specificity of 66.7%, Kappa: 0.618. The results are highly consistent. The model based on bone metastasis-associated biomarkers established in this study is useful in providing rationale for the screening, intervention and targeted therapy of bone metastasis in lung cancer. Although the results are interesting, the limitations of this study should be acknowledged. The patients enrolled into the prediction model and validation model were whole cohort of completed resected stage III patients, not including patients from other groups. Therefore, there might be selection bias in the model construction and results interpretation. The results might be more suitable to clinically stage III patients. Any generalization to other stages should not be expected. In the future, a bigger study with larger sample size with different stages, could help more objectively judge the value of this prediction model.

The bands were visualized by using the enhanced chemiluminescence system (Pierce, Rockford, IL). To validate the reproducibility, the tests were selleck repeated for at least 3 times. Statistical analysis Statistical analysis was performed using the independent 2-tailed t-test. All P values were two-tailed and considered statistically significantly if less than 0.05. Means, standard errors, and P values were calculated using SPSS version 11.0 for Windows. Results Cell transformation of IEC-6 cells The method has been well established

for cell transformation of normal cells with MNNG and PMA. We treated IEC-6 cells with MNNG and PMA for 12 times. After the final treatment, we detected the colony https://www.selleckchem.com/products/sbi-0206965.html formation in semisolidified agarose of normal and MNNG/PMA treated IEC-6 cells. Transformed foci of normal IEC-6 cells were 0.02% and that of MNNG/PMA treated IEC-6 cells were 0.37%. MNNG/PMA treatment markedly enhanced the production of

transformed foci (Table 3; p < 0.01). Table 3 Transformation of IEC-6 cells by MNNG and PMA1. Cell type dishes Number of clonies Clong efficiency in soft agar(%) normal 4 2 ± 0.1 0.02 MNNG/PMA 4 37 ± 0.2 0.37* * p < 0.01 compared to untreated cells. Then we detected the cell growth curve of normal and MNNG/PMA treated IEC-6 cells. Cell proliferation was determined by3H-TdR, which indicated the DNA synthesis. As shown in Fig. 1, cell growth of MNNG/PMA treated IEC-6 cells was significantly increased, compared with that of

normal IEC-6 cells. The increased cell growth was coincident with the property of cancer cells. To further confirm its cancerous character, MNNG/PMA treated IEC-6 cells were inoculated selleck products subcutaneously in nude mice. As expected, tumor xenografts oxyclozanide were detected in all animals 4 weeks later, which was coincident with the result of human cancer cell SW480. However, no tumor xenograft was visible in mice inoculated with normal IEC-6 cells even 8 weeks after inoculation. Fig. 1b showed the tumors were low- differentiated carcinomas. Histologically, the tumor cells of xenografts were arranged in flakiness and nest with round or polygon in shape. Tumor giant cells and mitotic phases could be seen. This suggested MNNG/PMA treated IEC-6 cells had been fully transformed. Figure 1 Transformation of normal ICE-6 cells. (A) Cell growth curves of normal and MNNG/PMA treated IEC-6 cells. (B) Histologically analysis of tumor xenografts inoculated with transformated IEC-6 cells. Changes of gene expression detected by microarray analysis To elucidate the molecular mechanisms involved in cell transformation of IEC-6 cells, the rat Oligo GEArray microarray was used to identify genes with altered expression level after cell tranformation, compared with its normal controls. The microarray comprised 113 genes representative of the six biological pathways involved in transformation and tumorigenesis.

For instance, in the wPip-Pel genome, the three pk1 and the three pk2 genes are spread among the five different prophages which are closely related to the WO-B wMel prophage [8]. Hence, the divergence in the pk1 and pk2 gene copy JNJ-26481585 in vitro number between Wolbachia MRT67307 strains may be explained by mechanisms related

to bacterial genome organization and modulation of gene copy number [26, 29–32]. As an example, two pseudogenes (wRi_ANK29 and ANK31) out the four copies of the pk1 gene in wRi, are spread in the WORiB prophage (previously annotated WO-C prophage [9], see Table 1) and may have originally been a single pk1 gene further disrupted by an insertion sequence ISWpi7. On the other hand, the high GC content of pk2 supports the occurrence of recent lateral transfers of prophage fragments containing the pk2 gene but not necessarily pk1 in the Wolbachia genomes. However, we cannot exclude the hypothesis that linkage disequilibrium occurs between pk1 and pk2 genes that are separated by at least 6.7 kilobases, representing less

than 0.04% of the whole genome size. These results also highlight the genomic plasticity of the prophage region among Wolbachia strains as part of the global plasticity observed in the Wolbachia genomes [33]. Maintenance of such “mobile elements” Selleckchem LY2603618 in Wolbachia strains of arthropods may be due to the absence of, or a reduced efficiency of selection on the prophages. Nevertheless, the purifying selection acting on these pk1 and pk2 genes suggest that maintenance of sequences confers an adaptive advantage. Besides identifying mosaic prophages, our results also reveal the differential expression of one pk2 ankyrin according to the Wolbachia phenotype they induce (CI vs. feminization). One allele (pk2b2) is only expressed in

the feminizing strains and never in the three CI-inducing strains of isopods. In contrast to the observations for wPip [22, 23], expression pattern of pk2b2 suggests that this allele is not involved in CI in isopods. In two recent studies, it has been shown that expression of pk1 and pk2 genes from wMel was not correlated with the CI phenotype in D. melanogaster[34, 35]. Our transcriptional result rather leads to the hypothesis that this pk2b2 allele is involved in the feminization of isopod hosts. This hypothesis is strengthened by the observation Phenylethanolamine N-methyltransferase that the pk2b2 allele is expressed in all A. vulgare tissues (except in the brain) whereas another prophage gene (orf7) is only expressed in ovaries. Furthermore, no differential expression of pk1 and pk2 genes was identified between sexes in isopods when either CI-inducing or feminizing Wolbachia infects both males and females. This result differs from those of Sinkins and colleagues who showed that in some CI-inducing wPip variants, the three pk2 genes (the two identical wPip_ANK12 and wPip_ANK25, and wPip_ANK16) are highly expressed in females but never in males [22, 23].

The whole obtained reaction product was purified by dialysis using a Spectra/Por MK-8931 purchase 3 dialysis membrane (Spectrum Laboratories Inc., Rancho Dominguez, CA, USA). Chemically exfoliated bulk h-BN The method of producing

chemically exfoliated h-BN is based upon the preparation of graphene oxide [36]. In a typical experiment, 0.75 g of h-BN bulk powder was dispersed in 60 ml of 96% H2SO4. Subsequently, 3 g of KMnO4 was added, and the reaction mixture was stirred under heating at 40°C continuously for 6 h. The obtained pink suspension was subsequently poured onto ice and mixed with 200 ml of 30% H2O2. The pink squash quickly changed to a white suspension, which was washed by decantation and centrifugation until it reached a pH ∼ 7.0. Characterization methods Diffraction

patterns were collected using a PANalytical X’Pert PRO diffractometer (Almelo, The Netherlands) equipped with a conventional X-ray tube (CuKα 40 kV, 30 mA, line focus) in the transmission mode. An elliptic focusing mirror with a divergence slit of 0.5°, an anti-scatter slit of 0.5°, and a Soller slit of 0.02 rad were used in the primary beam. A MLN2238 fast linear position-sensitive detector PIXcel with an anti-scatter shield and a Soller slit of 0.02 rad were used in the diffracted beam. All patterns were collected with steps of 0.013° and 500 s/step. A qualitative analysis was BI 2536 clinical trial performed with the DiffracPlus Eva software package (Bruker AXS, Berlin, Germany) using the JCPDS PDF-2 database [37]. A water suspension of the sample material was placed onto a sample holder for transmission experiments and then covered with a Mylar foil (6 μm thick, DuPont Tejjin Films, Chester, VA, USA). Then, the second Mylar foil covers the sample to avoid losses. Finally, the sample holder was completed with a sample holder

ring, making it ready for X-ray diffraction (XRD) experiments in transmission mode. The crystallite size, interlayer spacing, and number of h-BN and h-BCN layers were calculated by using the classical Debye-Scherrer equations [38, 39]. Atomic force microscopy (AFM) images were obtained using a Bruker Dimension FastScan microscope. The samples for AFM measurement Thalidomide were prepared through the spin coating method. The samples were prepared by pipetting the exfoliated h-BN and h-BCN water suspensions onto the synthetic mica as an atomically smooth support and then were spin-coated at 6,000 rpm for 1 min. A silicon tip on a nitride lever was used with ScanAsyst (Bruker) in the air contact mode for resonance frequencies ranging from 50 to 90 kHz. The morphology of the sample powders was inspected by transmission electron microscopy (TEM), and the crystal structure was analyzed by electron diffraction (ED) using a 300-kV JEOL 3010 (Akishima-shi, Japan).

It is significant to note that the two predominant amino acids produced in electric discharge experiments are glycine and alanine, the Strecker synthesis products of formaldehyde and acetaldehyde, respectively (Miller 1955). As suggested by Van Trump and Miller (1972), acrolein may have also played a key role as

a precursor in the formation of glutamic acid, homocysteine, homoserine and α,γ-diaminobutyric acid. Fig. 3 Prebiotic synthesis of methionine, methionine sulfoxide, methionine sulfone, ethionine, and homocysteic acid in the presence of acrolein, which is based in part on the scheme proposed by Van Trump ARRY-438162 and Miller (1972). Asterisks denote species that were detected in this study It has been suggested

that the reaction of ammonium thiocyanate, thiourea, and thiacetamide (all of which are produced from electric discharges acting on NH3, CH4, H2O, and H2S gas mixtures (Heyns et al. 1957)) with formaldehyde can lead to the production of glycine, cysteine, and cystine (Herrera 1942; Perezgasga et al. 2003). It has also been shown that H2S, together with pyrite and other metal sulfides, can partake in surface-mediated reactions that provide electrons for the reduction of organic compounds under simulated volcanic conditions (Huber et al. 2010; and references therein). However, organic sulfur-containing amino acids and amines, such as homocysteic acid, cysteamine, taurine (HO3SCH2CH2NH2) (Choughuley and Lemmon 1966), cysteine (Khare and Sagan 1971; Sagan and Khare 1971) and methionine, seem to be produced more readily

from model H2S-containing primitive atmospheres than from pyrite/metal selleck chemicals llc sulfide reactions (Huber et al. 2010). Two alternative pathways can be suggested for the production of cysteine from glycine under possible prebiotic conditions (Fig. 4). As suggested by Weber and Miller (1981), S-methylcysteine could have formed under primitive conditions by the Michael addition of CH3SH to dehydroalanine (Fig. 4). We could not confirm the formation of dehydroalanine because it is very reactive and thus if present its levels could be below our detection limits, which are in the low femtomole range. The notion that methionine is a product of the addition of CH3SH to acrolein L-gulonolactone oxidase (Van Trump and Miller 1972) is supported by the tentative detection of ethionine (Fig. 3), which could have been formed in part by the addition of ethane thiol (CH3CH2SH) to acrolein. Cysteamine has also been produced in a model reducing atmosphere with electron beams, albeit in low yields (Choughuley and Lemmon 1966). Several of the compounds we have detected are known decomposition products of cysteine and methionine. Cysteamine, the simplest aminothiol, is produced by the decarboxylation of cysteine (Fig. 4), and methionine sulfone and methionine sulfoxide are produced by the oxidation of methionine (ICG-001 Lieberman et al. 1965).

Authors’ contributions This work was finished through the collaboration of all authors. #AZD8931 purchase randurls[1|1|,|CHEM1|]# JLL carried out the calculation, analyzed the calculated data, and drafted the manuscript. TH helped analyze the data and participated in revising the manuscript. GWY supervised the work and finalized the manuscript. All authors read and approved the final manuscript.”
os A, Zou XD, Karlsson UO:

Self-assembled boron nanowire Y-junctions. Nano Lett 2006, 6:385–389.CrossRef 23. Cao LM, Zhang Z, Sun LL, Gao CX, He M, Wang YQ, Li YC, Zhang XY, Li G, Zhang J, Wang WK: Well-aligned boron nanowire arrays. Adv Mater 2001, 13:1701–1704.CrossRef 24. Sun LL, Matsuoka T, Tamari Y, Tian JF, Tian Y, Zhang CD, Shen CM, Yi W, Gao HJ, Li JQ, Dong XL, Zhao ZX: Pressure-induced superconducting state in crystalline boron nanowires. Selleck AZD2171 Phys Rev B 2009, 79:140505–140508. R. 25. Li ZZ, Baca J, Wu J: In situ switch of boron nanowire growth mode from vapor–liquid–solid to oxide-assisted growth. Appl Phys Lett 2008, 92:113104–113106.CrossRef 26. Yun SH, Wu JZ, Dibos A, Zou XD, Karlsson UO: Growth of inclined boron nanowire bundle arrays in an oxide-assisted vapor–liquid–solid process. Appl Phys Lett 2005, 87:113109–113111.CrossRef

27. Cao LM, Hahn K, Scheu C, Ruhle M, Wang YQ, Zhang Z, Gao CX, Li YC, Zhang XY, He M, Sun LL, Wang WK: Template-catalyst-free growth of highly ordered boron nanowire arrays. Appl Phys Lett 2002, 80:4226–4428.CrossRef 28. Setten MJV, Uijttewaal MA, Wijs GAD, Groot RAD: Thermodynamic stability of boron: the role of defects and zero point motion. J Am Chem Soc 2007, 129:2458–2465.CrossRef 29. Shang SL, Wang Y, Arroyave R, Liu ZK: Phase stability in α- and β-rhombohedral boron. Phys Rev B 2007, 75:092101–092104.CrossRef 30. Ordejón P, Artacho E, Soler JM: Self-consistent order-N density-functional calculations for very large systems. Phys Rev B 1996, 53:R10441-R10444.CrossRef 31. Sánchez-Portal D, Ordejón P, Artacho E, Soler JM: Density-functional method for very large systems with LCAO basis DOCK10 sets. Int J Quantum Chem 1997, 65:453–461.CrossRef

32. Soler JM, Artacho E, Gale JD, Garcia A, Junquera J, Ordejón P, Sánchez-Portal D: The SIESTA method for ab initio order-N materials simulation. J Phys Condens Matter 2002, 14:2745–2779.CrossRef 33. Troullier N, Martins JL: Efficient pseudopotentials for plane-wave calculations. Phys Rev B 1991, 43:1993–2006.CrossRef 34. Bylander DM, Kleinman L: 4f Resonances with norm-conserving pseudopotentials. Phys Rev B 1990, 41:907–912.CrossRef 35. Perdew JP, Burke K, Ernzerhof M: Generalized gradient approximation made simple. Phys Rev Lett 1996, 77:3865–3868.CrossRef 36. Monkhorst HJ, Pack JD: Special points for Brillouin-zone integrations. Phys Rev B 1976, 13:5188–5192.CrossRef 37. Zhang A, Zhu ZM, He Y, Ou YG: Structure stabilities and transitions in polyhedral metal nanocrystals: an atomic-bond-relaxation approach. Appl Phys Lett 2012, 100:1–5.

2.4.3 Image Analysis At the core laboratory, volume-rendering images, curved multi-planar reformation (MPR) images, interactive oblique MPR images, thin maximum intensity projection images, and cross-sectional images were prepared using the images reconstructed in the image analysis center of a third party. All images of each of 16

coronary segments based on the American Heart Association Classification were assessed and classified by the Central Selleck CB-839 Coronary Visualization Judgment Committee, consisting of three independent radiodiagnostic specialists, as the image quality score: Score 1—motion artifact(s) present and impossible to diagnose; Score 2—motion artifact(s) present but diagnosable; and Score 3—no motion artifact and diagnosable. The image quality score was analyzed per subject, per coronary vessel (total of four vessels: right coronary artery, left main coronary artery, left

anterior descending, and left circumflex) and per coronary segment. The validity of this assessment (comparison with coronary selleck angiographic findings) has already been confirmed by our phase II study [10]. Preparation of images as well as assessment of the diagnosable proportion were phosphatase inhibitor performed using a workstation Aquarius NET Server (Client PC networked with Aquarius NET Server) of the same model. 2.4.4 Statistical Analysis The analysis of efficacy and safety was based on the full analysis set (FAS). The changes in the heart Galeterone rate, blood pressure, and SpO2 were examined by t test. A p value of <0.05 was considered statistically significant. 3 Results A total of 39 subjects were enrolled and all subjects in this study received the study drug. During the

study period, two subject discontinued the study (due to exclusion criteria violation and failure of CT equipment). The FAS for the efficacy and safety analyses was thus composed of 39 subjects as planned. One subject who did not meet eligibility criteria was excluded from the per-protocol set. The analysis set for image evaluation of the mid-diastole images was composed of 25 subjects. The analysis set for image evaluation of an optimal image was composed of 26 subjects (Fig. 2). The radiation dose for the CCTA was 9.03 ± 1.27 mSv for patients. Fig. 2 Flow diagram of subjects 3.1 Baseline Characteristics The background factors and CCTA conditions of the subjects enrolled in the present study are summarized in Table 2. Age [mean ± standard deviation (SD)] was 65.7 ± 10.3 years. Heart rate (mean ± SD) immediately before administration of the study drug was 77.1 ± 9.8 beats/min. Systolic blood pressure (mean ± SD) immediately before administration of the study drug was 128.7 ± 15.3 mmHg. The number of subjects by CT model was 16 for Siemens (16-slice), 14 for GE (16), and nine for Toshiba (16), respectively. The number (%) of subjects with concomitant use of oral β-blockers was three (7.7 %).

Appl Environ Microbiol 2002, 68:673–690.PubMedCrossRef Authors’ contributions LH conceived and designed the study, collected and prepared the tissues, performed Fluorescence Givinostat ic50 In Situ Hybridisation and drafted the manuscript. TKJ and LM assisted in designing the study, making microscopic images, performed the cloning and sequencing and drafted the manuscript. SNO participated in designing the study and helped draft the manuscript. All authors read and approved the

final manuscript.”
“Background Chlamydia trachomatis is an intracellular bacterium that can multiply only within a host cell. Reticulate bodies (RBs) are the replicating form of Chlamydia bacteria that transform into infectious elementary bodies (EBs) prior to cell lysis. The transformation from a fragile RB to a robust EB is dramatic: the size reduces from 1 μm to 0.3 μm, the dispersed chromatin aggregates into a condensed nucleoid and metabolism ceases. C. trachomatis is classified into 19 serotypes (A-L3) based on the major outer membrane protein (MOMP) where PFT�� research buy A-C cause trachoma, D-K cause urogenital infections and L1-L3 cause lymphogranuloma venereum (LGV). Hc1 and Hc2 are DNA-binding proteins, homologous to eukaryotic histone H1 [1, 2] which are thought to mediate the chromatin compaction. These histone-like proteins are encoded by the hctA and hctB genes that are expressed late in the life cycle when

RBs convert to EBs [3]. The hctA gene Suplatast tosilate has been inserted into Escherichia coli and the expressed Hc1 was shown to induce a compaction of chromatin into a spherical condensed nucleoid [4]. Hc2 also condenses DNA but the nucleoid is distinctly different with a more thoroid shape [5, 6], indicating that these proteins interact with DNA in different ways. Both proteins are able to repress transcription, but Hc2 has a higher binding affinity for RNA and thus represses translation more efficiently than Hc1 [6]. The Hc1 protein has two domains: the conserved N-terminus [7], which mediates dimerisation, and the lysine-rich C-terminus, which is responsible for DNA binding [8,

9]. Hc2, on the other hand, varies in size between serovars because of varying numbers of lysine-rich pentameric repeats [10]. Hc2 appears to be ubiquitous in Chlamydiaceae because the hctB gene has been found in all available genome sequences of this family, Based on Southwestern blot analysis, Hc2 has previously been reported to be absent or present in reduced amounts in Chlamydophila psittaci Tariquidar strain Mn [10]. However, the hctB gene has been found in C. psittaci strain 6BC by whole genome sequencing (G. Myers, personal communication). The hctB gene encoding Hc2 is one of the targets in a newly developed multilocus sequence typing (MLST) system for C. trachomatis [11]. Studies of trachoma, lymphogranuloma venereum (B.

For both logos, the width of the vertical red bars is proportional to the frequency of an insertion at that MEK inhibitor position in the model. The width of the subsequent vertical pink bar is proportional to the length of that insertion [Figures prepared using MUSCLE (Edgar 2004), HMMER 3.0 (Eddy 1998), and LogoMat-M (Schuster-Bockler et al. 2004)] Fig. 5 Schematic model of the α-carboxysome assembly containing RuBisCO small (dark green) and large (green) subunits and carbonic anhydrase (red). The shell is composed of hexamers (blue), pseudohexamers (light blue, magenta, and light green), and pentamers (yellow) The structures of the BMC domain: a key building block of the carboxysome shell The

first structures determined from the carboxysome shell were the CcmK2 and CcmK4 proteins from the carboxysome of the β-cyanobacteria this website Vorinostat mw Synechocystis sp. PCC6803 (Kerfeld et al. 2005). The structures revealed that the BMC domain forms hexamers with a disk-like shape, giving each a concave and a convex side (Fig. 6). Packing of the hexamers in some of the crystal forms immediately suggested a model for the underlying architecture of the carboxysome shell: the shell proteins formed a two-dimensional layer similar to hexagonal tiles (Fig. 5). CcmK2 formed a uniform layer with all hexamer faces oriented in the same direction whereas CcmK4, in one of two crystal

forms, formed a layer with strips of hexamers alternating between convex and concave orientations (Kerfeld et al. 2005). Fig. 6 Electrostatic comparison of structurally characterized single-domain BMC [PDB:3BN4 (CcmK1), 2A1B (CcmK2), 2A10 (CcmK4), 2G13 (CsoS1A), 3H8Y (CsoS1C)] proteins and pentameric shell proteins [PDB:2QW7 (CcmL), 2RCF (CsoS4A)]. Convex (top), concave (middle), and pore cross-section (bottom) views are shown for each structure. heptaminol Red denotes negative charge; blue denotes positive charge [Figure generated with APBS Plug-in (Baker et al. 2001) for PyMOL] Crystal structures of the CsoS1A (Tsai et al. 2007) and CsoS1C (Tsai et al. 2009) proteins from the α-carboxysome

of Halothiobacillus neapolitanus have also been determined. These displayed the same concave/convex sidedness and uniformly oriented layer formation as observed for CcmK2. Despite a high degree of sequence homology between CsoS1A and CsoS1C (97% identity), a comparison of the electrostatics of these structures shows a difference in the charge distribution on the concave faces (Fig. 6). There is a single amino acid substitution between CsoS1A and CsoS1C at position 97 (from Glu to Gln) that apparently accounts for this difference in electrostatic potential. A superposition of all the single-domain carboxysome BMC protein structures show they share a conserved fold [root mean square deviation (RMSD) range of 0.36–0.71 Å over 66–86 C-α atoms] with only slight differences between the Cso-type homologs from the α-carboxysomes and the Ccm-type homologs from the β-carboxysome (Fig. 7).