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The aim of this study was to investigate environmental conditions affecting chicken feather degradation and keratinolytic enzyme production by Bacillus megaterium F7-1, a feather-degrading mesophilic bacterium. B. megaterium F7-1 degraded whole chicken feather completely within 7 days. The bacterium grew with an optimum at pH 7.0-11.0 and 25-40 degrees C, where maximum keratinolytic activity was also observed. The production of keratinolytic enzyme by B. megaterium F7-1 was inducible with feather. Keratinolytic enzyme production by B. megaterium F7-1 at 0.6% (w/v) skim milk was 468U/ml, which was about 9.4-fold higher than that without skim milk. The amount of keratinolytic enzyme production depended on feather concentrations. The degradation rate of autoclaved chicken feathers by cell-free culture supernatant was 26% after 24h of incubation, but the degradation of untreated chicken feathers was unsuccessful. B. megaterium F7-1 effectively degraded feather meal, duck feather and human nail, whereas human hair and sheep wool showed relatively low degradation rates. B. megaterium F7-1 presented high keratinolytic activity and was very effective in feather degradation, providing potential use for biotechnological processes of keratin hydrolysis.

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AMPK/Nrf2 signaling regulates multiple antioxidative factors and exerts neuroprotective effects. Emodin is one of the main bioactive components extracted from Polygonum multiflorum, a plant possessing important activities for human health and for treating a variety of diseases. This study examined whether emodin can activate AMPK/Nrf2 signaling and induce the expression of genes targeted by this pathway. In addition, the anti-neuroinflammatory properties of emodin in lipopolysaccharide (LPS)-stimulated microglia were examined. In microglia, the emodin treatment increased the levels of LKB1, CaMKII, and AMPK phosphorylation. Emodin increased the translocation and transactivity of Nrf2 and enhanced the levels of HO-1 and NQO1. In addition, the emodin-mediated expression of HO-1 and NQO1 was attenuated completely by an AMPK inhibitor (compound C). Moreover, emodin decreased dramatically the LPS-induced production of NO and PGE as well as the protein expression and promoter activity of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In addition, emodin effectively inhibited the production of pro-inflammatory cytokines, TNF-α and IL-6, and reduced the level of IκBα phosphorylation, leading to the suppression of the nuclear translocation, phosphorylation, and transactivity of NF-κB. Emodin also suppressed the LPS-stimulated activation of STATs, JNK, and p38 MAPK. The anti-inflammatory effects of emodin were reversed by transfection with Nrf-2 and HO-1 siRNA and by a co-treatment with an AMPK inhibitor. These results suggest that emodin isolated from P. multiflorum can be used as a natural anti-neuroinflammatory agent that exerts its effects by inducing HO-1 and NQO1 via AMPK/Nrf2 signaling in microglia.

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The gene for a thermostable beta-agarase from Agarivorans sp. JA-1 was cloned and sequenced. It comprised an open reading frame of 2,988 base pairs, which encode a protein of 109,450 daltons consisting of 995 amino acid residues. A comparison of the entire sequence showed that the enzyme has 98.8% sequence similarities to beta-agarase from Vibrio sp. JT1070, indicating that it belongs to the family glycoside hydrolase (GH)-50. The gene corresponding to a mature protein of 976 amino acids was inserted and expressed in Escherichia coli. The recombinant beta-agarase was purified to homogeneity. It had maximal activity at 40 degrees C and pH 8.0 in the presence of 1 mM NaCl and 1 mM CaCl(2). The enzyme hydrolyzed agarose as well as neoagarohexaose and neoagarotetraose to yield neoagarobiose as the main product. Thus, the enzyme would be useful for the industrial production of neoagarobiose.

Gold nanoparticles (AuNPs) with antitumorigenic effects obstruct the initiation, development and progression of tumors via the regulation of various processes, such as proliferation and apoptosis. However, the effects of AuNPs on breast cancer metastasis have not been well studied, and their response to 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulation remains unclear. Therefore, we synthesized resveratrol-capped gold nanoparticles (Rev-AuNPs) using green nanotechnology and investigated their potential anti-invasive properties in human breast cancer cells in response to TPA stimulation. The Rev-AuNPs formed spherical nanoparticles of 22.28±2.98 nm in diameter. Next, we found that non-cytotoxic concentrations of Rev-AuNPs significantly suppressed the TPA-induced migration and invasion abilities of breast cancer cells. Rev-AuNPs suppressed TPA-induced enzymatic activity and the expression of matrix metalloproteinase (MMP)-9 and cyclooxygenase-2 (COX-2). Furthermore, Rev-AuNP treatment remarkably downregulated TPA-induced nuclear translocation and transcriptional activation of nuclear transcription factor-κB (NF-κB) and activator protein-1 (AP-1). Rev-AuNPs reduced the phosphorylation of phosphoinositide 3-kinase/Akt (PI3K/Akt) and extracellular signal-regulated kinase (ERK)1/2 signaling, but did not affect the phosphorylation of Jun N-terminal kinase (JNK) or p38 MAPK in the TPA-stimulated breast cancer cells. Notably, Rev-AuNPs generally showed better anti-invasive activity than resveratrol without cytotoxicity. The inhibitory effect of Rev-AuNPs on MMP-9, COX-2, NF-κB, AP-1, PI3K/Akt and ERK activation was stronger than that of resveratrol for the same concentrations. We also demonstrated that Rev-AuNPs induced heme oxygenase-1 (HO-1) expression and that the inhibition of MMP-9 and COX-2 expression and MMP-9 enzymatic activity of Rev-AuNPs were abrogated by siRNA knockdown of HO-1 expression. Our findings revealed that the anti-invasive effects of Rev-AuNPs in response to TPA-stimulation were mediated by the suppression of MMP-9, COX-2, NF-κB, AP-1, PI3K/Akt and ERK and/or the activation of HO-1 signaling cascades. This novel finding emphasizes the pharmacological ability of Rev-AuNPs to treat breast cancer metastasis.

Controlling the assembly of basic structural building blocks in a systematic and orderly fashion is an emerging issue in various areas of science and engineering such as physics, chemistry, material science, biological engineering, and electrical engineering. The self-assembly technique, among many other kinds of ordering techniques, has several unique advantages and the M13 bacteriophage can be utilized as part of this technique. The M13 bacteriophage (Phage) can easily be modified genetically and chemically to demonstrate specific functions. This allows for its use as a template to determine the homogeneous distribution and percolated network structures of inorganic nanostructures under ambient conditions. Inexpensive and environmentally friendly synthesis can be achieved by using the M13 bacteriophage as a novel functional building block. Here, we discuss recent advances in the application of M13 bacteriophage self-assembly structures and the future of this technology.