Theoretical calculation of the sugar concentrations during enzymatic production of fructooligosaccharides

Summary In a batch production of fructooligosaccharides from sucrose, the concentrations of residual sucrose, glucose and fructooligosaccharides at a given reaction time(t) and initial sucrose concentration(S₀) were theoretically calculated by the following correlation equations: Glucose(t) = 0.0653 S₀ × ln(t); Fructooligosaccharides(t) = 0.1636 S₀ × ln(t); Sucrose(t)=S₀ - Glucose(t) + FOS(t).     

Design,synthesis, and evaluation of curcumin analogues as potential inhibitors of bacterial sialidase

Sialidases are key virulence factors that remove sialic acid from the host cell surface glycan, unmasking receptors that facilitate bacterial adherence and colonisation. In this study, we developed potential agents for treating bacterial infections caused by Streptococcus pneumoniae Nan A that inhibit bacterial sialidase using Turmeric and curcumin analogues. Design, synthesis, and structure analysis relationship (SAR) studies have been also described. Evaluation of the synthesised derivatives demonstrated that compound 5e was the most potent inhibitor of S. pneumoniae sialidase (IC₅₀?=?0.2?±?0.1?µM). This compound exhibited a 3.0-fold improvement in inhibitory activity over that of curcumin and displayed competitive inhibition. These results warrant further studies confirming the antipneumococcal activity 5e and indicated that curcumin derivatives could be potentially used to treat sepsis by bacterial infections.     

Recording of elapsed time and temporal information about biological events using Cas9

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Plant gene responses to frequency-specific sound signals

We identified a set of sound-responsive genes in plants using a sound-treated subtractive library and demonstrated sound regulation through mRNA expression analyses. Under both light and dark conditions, sound up-regulated expression of rbcS and ald. These are also light-responsive genes and these results suggest that sound could represent an alternative to light as a gene regulator. Ald mRNA expression increased significantly with treatment at 125 and 250 Hz, whereas levels decreased significantly with treatment at 50 Hz, indicating a frequency-specific response. To investigate whether the ald promoter responds to sound, we generated transgenic rice plants harboring a chimeric gene comprising a fusion of the ald promoter and GUS reporter. In three independent transgenic lines treated with 50 or 250 Hz for 4 h, GUS mRNA expression was up-regulated at 250 Hz, but down-regulated at 50 Hz. Thus, the sound-responsive mRNA expression pattern observed for the ald promoter correlated closely with that of ald, suggesting that the 1,506 bp ald promoter is sound-responsive. Therefore, we propose that in transgenic plants, specific frequencies of sound treatment could be used to regulate the expression of any gene fused to the ald promoter.     

Mapping the human CAS2 gene, the homologue of the mouse brown (b) locus, to human chromosome 9p22-pter

Melanin biosynthesis is a multistep process with the first step being the conversion of L-tyrosine to L-Dopa catalyzed by the enzyme tyrosinase. The enzymes which catalyze the other steps of melanogenesis are not known. One murine pigmentation gene, the brown (b) locus, when mutated, leads to a brown or hypopigmented coat. The b-locus protein has been shown to display catalase activity. The human b-locus, therefore, is designated as CAS2. We used the mouse b-locus cDNA to isolate the human homologue, which in turn, was used to map the CAS2 locus to a human chromosome. The potential CAS2 protein codes for 527 amino acids containing a putative signal sequence and transmembrane domain. The CAS2 protein has primary and probably secondary structures similar to human tyrosinase. The CAS2 was mapped to human Chromosome 9 by somatic cell hybridization and, more specifically, to 9p22-pter by in situ hybridization. The assignment of CAS2 on the human Chromosome 9 extends this region of known homology on mouse Chromosome 4.     

Growth medium sterilization using decomposition of peracetic acid for more cost-efficient production of omega-3 fatty acids by Aurantiochytrium

Bioprocess and Biosystems Engineering - Aurantiochytrium can produce significant amounts of omega-3 fatty acids, specifically docosahexaenoic acid and docosapentaenoic acid. Use of a glucose-based...     

Taxonomic revision of the genus Jassidophaga Aczél (Diptera: Pipunculidae) in Korea

In this paper, three Korean species of the big‐head fly, genus Jassidophaga Aczél were treated: J. chiiensis (Ouchi), J. pala (Morakote) and J. villosa (Roser). Of these, J. pala is reported in Korea for the first time. A key to Korean species and photographs on external features are given.     

Inhibition of Cell Proliferation and Migration by miR-509-3p That Targets CDK2, Rac1, and PIK3C2A

CDK2 is a key regulator of cell cycle progression. In this study, we screened for miRNAs targeting CDK2 using a luciferase-3′-untranslated region reporter assay. Among 11 hit miRNAs, miR-509-3p reduced CDK2 protein levels and significantly inhibited cancer cell growth. Microarray, Western blotting, and luciferase reporter analyses revealed additional targets of miR-509-3p, including Rac1 and PIK3C2A. Overexpression of miR-509-3p induced G1 cell-cycle arrest and inhibited colony formation and migration. RNAi experiments indicated that the growth-inhibitory effects of miR-509-3p may occur through down-regulation of CDK2, Rac1, and PIK3C2A. Targeting of multiple growth regulatory genes by miR-509-3p may contribute to effective anti-cancer therapy.