Objective. To evaluate associations of genetic polymorphisms in cytochrome P450 (CYP) isoforms 2D6, 3A5, and 3A4 with blood concentrations of hydroxychloroquine (HCQ) and its metabolite, N-desethyl HCQ (DHCQ), in patients with systemic lupus erythematosus (SLE).Methods. SLE patients taking HCQ for >3 months were recruited and were genotyped for 4 single-nucleotide polymorphisms in CYP2D6*10, CYP3A5*3, and CYP3A4* 18B. Blood HCQ and DHCQ concentrations ([HCQ] and [DHCQ]) were measured and their association with corresponding genotypes was investigated.Results. A total of 194 patients were included in the analysis. CYP2D6*10 polymorphisms (rs1065852 and rs1135840) were significantly associated with the [DHCQ]:[HCQ] ratio after adjustment for age, sex, dose per weight per day, and SLE Disease Activity Index score (P 5 0.03 and P < 0.01, respectively). In adjusted models, the [DHCQ]:[HCQ] ratio was highest in patients with the G/G genotype of the CYP2D6*10 (rs1065852) polymorphism and lowest in those with the A/A genotype (P 5 0.03). Similarly, the [DHCQ]:[HCQ] ratio was highest in patients with the C/C genotype of the CYP2D6*10 (rs1135840) polymorphism and lowest in those with the G/G genotype (P < 0.01). The CYP2D6*10 (rs1065852) polymorphism was significantly related to the [DHCQ] (P 5 0.01). However, the polymorphisms of CYP3A5*3 and CYP3A4*18B did not show any significant association with the Hydroxychloroquine (HCQ) is an antimalarial drug that is proven to be a safe and effective treatment for systemic lupus erythematosus (SLE) (1). Despite its wide application, only a few studies have previously measured blood HCQ levels in patients taking the drug in the long term. Interestingly, blood HCQ levels vary widely between patients, even those taking the same dose at the same frequency (2-7). This interpersonal variation is not well understood. However, the blood HCQ concentration is closely related to the treatment response in autoimmune diseases such as SLE (4,5,8,9). Therefore, identifying factors related to variations in blood levels is critical to maximize the benefit of HCQ in SLE patients.Cytochrome P450 (CYP) enzymes play major roles in drug metabolism. Certain single-nucleotide polymorphisms (SNPs) in CYP genes may have a large impact on CYP enzyme activity. HCQ is metabolized to N-desethyl HCQ (DHCQ) in the liver through the Ndesethylation pathway (10,11). This reaction is mediated by CYP 2D6, 3A4, 3A5, and 2C8 isoforms (11-13).

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Carbonic anhydrase enzyme, one of the fastest known enzymes, remains largely unexplored in prokaryotes when compared to its mammalian counterparts despite its ubiquity. In this study, the enzyme has been purified from Bacillus subtilis SA3 using sequential Sephadex G-75 chromatography, DEAE cellulose chromatography, and sepharose-4B-L-tyrosinesulphanilamide affinity chromatography and characterized to provide additional insights into its properties. The apparent molecular mass of carbonic anhydrase obtained by SDS-PAGE was found to be approximately 37 kDa. Isoelectric focusing of the purified enzyme revealed an isoelectric point (pI) of around 6.1 when compared with marker. The presence of metal ions such as Zn, and anion SO 4 − increased enzyme activity while strong inhibition was observed in the presence of Hg 2+ , Cl − , HCO 3 − , and metal chelator EDTA. The optimum pH and temperature for the enzyme were found to be 8.3 and 37°C, respectively. Enzyme kinetics with p-nitrophenyl acetate as substrate at pH 8.3 and 37°C determined the V max and K m values of the enzyme to be 714.28 µmol/mg protein/min and 9.09 mM, respectively. The K i value for acetazolamide was 0.22 mM, compared to 0.099 mM for sulphanilamide. The results from N-terminal amino acid sequencing imply the purified protein is a putative beta-carbonic anhydrase with close similarities to CAs from plants, microorganisms. © KSBB

C-reactive protein (CRP) is a general marker of systemic inflammation and cardiovascular disease (CVD). The genetic contribution to differences in CRP levels remains to be explained, especially in non-European populations. Thus, the aim of this study was to identify genetic loci associated with CRP levels in Korean population. We performed genome-wide association studies (GWAS) using SNPs from 8,529 Korean individuals (7,626 for stage 1 and 903 for stage 2). We also performed pathway analysis. We identified a new genetic locus associated with CRP levels upstream of ARG1 gene (top significant SNP: rs9375813, Pmeta = 2.85×10−8), which encodes a key enzyme of the urea cycle counteract the effects of nitric oxide, in addition to known CRP (rs7553007, Pmeta = 1.72×10−16) and HNF1A loci (rs2259816, Pmeta = 2.90×10−10). When we evaluated the associations between the CRP-related SNPs with cardiovascular disease phenotypes, rs9375813 (ARG1) showed a marginal association with hypertension (P = 0.0440). To identify more variants and pathways, we performed pathway analysis and identified six candidate pathways comprised of genes related to inflammatory processes and CVDs (CRP, HNF1A, PCSK6, CD36, and ABCA1). In addition to the previously reported loci (CRP, HNF1A, and IL6) in diverse ethnic groups, we identified novel variants in the ARG1 locus associated with CRP levels in Korean population and a number of interesting genes related to inflammatory processes and CVD through pathway analysis.

Carbon concentrating mechanisms play a vital role in photosynthesis in microalgae and cyanobacteria especially in the proper functioning of Rubisco and assimilation of carbon via the Calvin cycle. This study evaluates the role of carbon dioxide on carbon concentrating mechanism (CCM) in a cynaobacteria, Spirulina platensis and a microalga, Chlorella sp. 786. The study organisms were grown in both atmospheric (control sample, 0.035%) and high (exposed sample, 10%) CO 2 concentrations. Second dimension (2D) electrophoresis revealed a huge difference in the protein profiles of both organisms suggesting the induction of CCM related proteins in the sample maintained at atmospheric CO 2 concentration and the repression of CCM related proteins in the sample maintained at 10% CO 2 . Liquid chromatography-mass spectroscopy analysis revealed the presence of two important C i transporter proteins in the control sample of S. platensis, namely ferredoxin-NADP + reductase and ATP binding cassette (ABC) transport system protein. These proteins were only expressed in the control sample and were downregulated or not expressed at all in the exposed sample. Consequently, this study conclusively proves that CCMs are only inducted at low CO 2 concentrations and are not functional at high CO 2 concentration.Key Words: carbon concentrating mechanism (CCM); Chlorella sp.; cyanobacteria; proteomics; Rubisco; Spirulina platensis INTRODUCTIONNatural photosynthesis in green plants achieves carbon dioxide (CO 2 ) fixation on a global scale. The incorporation of CO 2 into the biosphere by the photosynthetic action of plants and microorganisms has been estimated to amount to about 10 11 tons of CO 2 per year Somanchi 1999, Prentice 2001). However, the efficiency of solar energy conversion in plant production under optimal growth conditions is only 5-6%. The global average efficiency has been estimated as 0.15% (Price et al. 2008). Photosynthesis is much more efficient in single celled organisms such as microalgae and cyanobacteria than in terrestrial C 3 and C 4 plants ( Kaplan and Reinhold 1999). This high efficiency is primarily due to two factors: the action of carbonic anhydrase (CA), both extracellular and intracellular, and the CO 2 concentrating mechanisms (CCM) ( Van et al. 2001, Spalding et al. 2002, Vance and Spalding 2005. CO 2 concentration plays a vital role in the induction or repression of CCM in microalgae and cyanobacteria. It has been proven that CCM is induced in low CO 2 concentrations, however, there is little informa- 296exposed sample was maintained at a CO 2 concentration of 10% (10,000 ppm). Both the cultures were grown for a period of 15-20 days in the reactor (Ramanan et al. 2010).The algal cells were centrifuged at 5,000 ×g for 5 min and to 0.5 g of algal pellet, 10 mL of algal culture medium with 2% Triton X-100 was added. The algal pellet was resuspended and pelleted. Supernatant which had greenish-yellow tint was poured off. The pellet was once again rinsed with culture medium and centrifuged again. The super...

The findings in this article suggest that occupational exposure to diesel exhaust of engine tuning workers causes induction of oxidative stress, which cannot be correlated with the heavy metals status in blood and urine of an exposed population.

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Calcium is a universal intracellular messenger that has an important role in controlling various cellular processes. In this study, we explored genetic polymorphisms to identify novel loci influencing serum calcium levels in East Asians through a two-stage genome-wide association study with the sample of 8642 unrelated Koreans (4558 for discovery and 4093 for replication). Using single-nucleotide polymorphism (SNP) arrays, we discovered 963 associated SNPs in stage 1, and replicated 105 SNPs among them in stage 2. We examined them in a combined set of stage 1 and 2 samples and observed that 65 SNPs were significantly associated with serum calcium levels. Among them, rs13068893 in the CASR gene showed the strongest significance (P=3.85 × 10(-8)). Considering the high allele frequency and significance level of the rs13068893C>G in the CASR gene, this SNP may have a key role in regulating the serum calcium level. We also successfully replicated the four loci (CASR, CSTA, DGKD and GCKR) using our data set that have been previously reported to be significantly associated with calcium levels in Europeans and Indians. Further studies with more East Asian subjects or meta-analyses on them may enable validation of our results and identification of novel genetic loci associated with serum calcium levels.