A Functional Polymorphism Downstream of Vitamin A Regulator Gene CYP26B1 Is Associated with Hand Osteoarthritis.

While genetic analyses have revealed ~100 risk loci associated with osteoarthritis (OA), only eight have been linked to hand OA. Besides, these studies were performed in predominantly European and Caucasian ancestries. Here, we conducted a genome-wide association study in the Han Chinese population to identify genetic variations associated with the disease. We recruited a total of 1136 individuals (n = 420 hand OA-affected; n = 716 unaffected control subjects) of Han Chinese ancestry. We carried out genotyping using Axiom Asia Precisi on Medicine Research Array, and we employed the RegulomeDB database and RoadMap DNase I Hypersensitivity Sites annotations to further narrow down our potential candidate variants. Genetic variants identified were tested in the Geisinger's hand OA cohort selected from the Geisinger MyCode community health initiative (MyCode®). We also performed a luciferase reporter assay to confirm the potential impact of top candidate single-nucleotide polymorphisms (SNPs) on hand OA. We identified six associated SNPs (p-value = 6.76 × 10-7-7.31 × 10-6) clustered at 2p13.2 downstream of the CYP26B1 gene. The strongest association signal identified was rs883313 (p-value = 6.76 × 10-7, odds ratio (OR) = 1.76), followed by rs12713768 (p-value = 1.36 × 10-6, OR = 1.74), near or within the enhancer region closest to the CYP26B1 gene. Our findings showed that the major risk-conferring CC haplotype of SNPs rs12713768 and rs10208040 [strong linkage disequilibrium (LD); D' = 1, r2 = 0.651] drives 18.9% of enhancer expression activity. Our findings highlight that the SNP rs12713768 is associated with susceptibility to and severity of hand OA in the Han Chinese population and that the suggested retinoic acid signaling pathway may play an important role in its pathogenesis.

Prevalence and characterization of Ice Nucleation Active (INA) bacteria from rainwater in Indonesia.

BACKGROUND: Ice nucleation active (INA) bacteria are a group of microorganisms that can act as biological nucleator due to their ice nucleation protein property. Unfortunately, little is known about their prevalence and characteristics in tropical areas including Indonesia. Here, we monitor the presence of INA bacteria in rainwater and air samples collected from Jakarta, Tangerang and several areas in Western Java, Indonesia for one year. We further identify and characterize selected Class A of INA bacteria isolated from these areas. RESULTS: Most of the INA bacteria were isolated from rainwater samples collected during March-August 2010, particularly from Jakarta, Bandung, and Tangerang. A total of 1,902 bacterial isolates were recovered from these area. We found a limited number of bacterial isolates from air sampling. From ice nucleation activity assays, 101 INA isolates were found active as ice nucleator at a temperature above -10 °C. A large majority (73 isolates) of them are classified as Class C (active below -8 °C), followed by Class A (26 isolates; active at -2 to -5 °C) and Class B (two isolates; active at -5 to -8 °C). We sequenced the 16S rRNA gene of 18 Class A INA isolates and identified 15 isolates as Enterobacteriaceae, while the remaining three as Pseudomonadaceae. The vast majority of our Class A INA isolates were likely Pantoea spp. with several isolates were deduced as either Pseudomonas, Cronobacter, and Klebsiella. We found that these 18 Class A INA isolates had acquired resistance to antibiotics erythromycin and ampicillin, which are considered two critically important antibiotics. CONCLUSIONS: Our results showed that the prevalence of INA bacterial population varies across locations and seasons. Furthermore, our isolates were dominated by Class A and C INA bacteria. This study also cautions regarding the spread of antibiotic resistance among INA bacteria.

Gene cloning and catalytic characterization of cold-adapted lipase of Photobacterium sp. MA1-3 isolated from blood clam.

A lipase-producing Photobacterium strain (MA1-3) was isolated from the intestine of a blood clam caught at Namhae, Korea. The lipase gene was cloned by shotgun cloning and encoded 340 amino acids with a molecular mass of 38,015 Da. It had a very low sequence identity with other bacterial lipases, with the exception of that of Photobacterium lipolyticum M37 (83.2%). The MA1-3 lipase was produced in soluble form when Escherichia coli cells harboring the gene were cultured at 18°C. Its optimum temperature and pH were 45°C and pH 8.5, respectively. Its activation energy was calculated to be 2.69 kcal/mol, suggesting it to be a cold-adapted lipase. Its optimum temperature, temperature stability, and substrate specificity were quite different from those of M37 lipase, despite the considerable sequence similarities. Meanwhile, MA1-3 lipase performed a transesterification reaction using olive oil and various alcohols including methanol, ethanol, 1-propanol, and 1-butanol. In the presence of t-butanol as a co-solvent, this lipase produced biodiesel using methanol and plant or waste oils. The highest biodiesel conversion yield (73%) was achieved using waste soybean oil and methanol at a molar ratio of 1:5 after 12 h using 5 units of lipase.

Characterization of lipases from Staphylococcus aureus and Staphylococcus epidermidis isolated from human facial sebaceous skin.

Two staphylococcal lipases were obtained from Staphylococcus epidermidis S2 and Staphylococcus aureus S11 isolated from sebaceous areas on the skin of the human face. The molecular mass of both enzymes was estimated to be 45 kDa by SDS-PAGE. S2 lipase displayed its highest activity in the hydrolysis of olive oil at 32 degrees C and pH 8, whereas S11 lipase showed optimal activity at 31 degrees C and pH 8.5. The S2 lipase showed the property of cold-adaptation, with activation energy of 6.52 kcal/mol. In contrast, S11 lipase's activation energy, at 21 kcal/mol, was more characteristic of mesophilic lipases. S2 lipase was stable up to 45° C and within the pH range from 5 to 9, whereas S11 lipase was stable up to 50 degrees C and from pH 6 to 10. Both enzymes had high activity against tributyrin, waste soybean oil, and fish oil. Sequence analysis of the S2 lipase gene showed an open reading frame of 2,067 bp encoding a signal peptide (35 aa), a pro-peptide (267 aa), and a mature enzyme (386 aa); the S11 lipase gene, at 2,076 bp, also encoded a signal peptide (37 aa), pro-peptide (255 aa), and mature enzyme (399 aa). The two enzymes maintained amino acid sequence identity of 98-99% with other similar staphylococcal lipases. Their microbial origins and biochemical properties may make these staphylococcal lipases isolated from facial sebaceous skin suitable for use as catalysts in the cosmetic, medicinal, food, or detergent industries.