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L-Lysine is a potential feedstock for the production of bio-based precursors for engineering plastics. In this study, we developed a microbial process for high-level conversion of L-lysine into 5-aminovalerate (5AVA) that can be used as a monomer in nylon 6,5 synthesis. Recombinant Escherichia coli WL3110 strain expressing Pseudomonas putida delta-aminovaleramidase (DavA) and lysine 2-monooxygenase (DavB) was grown to high density in fed-batch culture and used as a whole cell catalyst. High-density E. coli WL3110 expressing DavAB, grown to an optical density at 600 nm (OD600 ) of 30, yielded 36.51 g/L 5AVA from 60 g/L L-lysine in 24 h. Doubling the cell density of E. coli WL3110 improved the conversion yield to 47.96 g/L 5AVA from 60 g/L of L-lysine in 24 h. 5AVA production was further improved by doubling the L-lysine concentration from 60 to 120 g/L. The highest 5AVA titer (90.59 g/L; molar yield 0.942) was obtained from 120 g/L L-lysine by E. coli WL3110 cells grown to OD600 of 60. Finally, nylon 6,5 was synthesized by bulk polymerization of ϵ-caprolactam and δ-valerolactam prepared from microbially synthesized 5AVA. The hybrid system demonstrated here has promising possibilities for application in the development of industrial bio-nylon production processes.

Abstract. Osteopontin (OPN, SPP1) is a secretory extracellular matrix protein that has been implicated in cancerassociated mechanisms such as metastasis, invasion and angiogenesis. Three OPN isoforms (OPN-a, -b and -c) derived from alternative splicing are known to exist, but their functional specificity remains unclear. Here, we found that the expression profile of OPN isoforms in hepatocellular carcinoma (HCC) cell lines and patient tissues were correlated with specific cellular phenotypes and tumorigenicity of HCC. Thus, SK-Hep1 cells with a robust migratory capacity dominantly expressed both OPN-a and -b, but non-migratory cell lines such as Hep3B and PLC/PRF/5 mainly expressed OPN-c. Moreover, tumor tissues predominantly expressed OPN-a and -b, whereas normal liver tissues mainly expressed OPN-c. Transwell infiltration and wound-induced migration assays revealed that both OPN-a and -b induced Hep3B cell migration, while OPN-c had no significant effects. By contrast, OPN-c suppressed the migratory activity of SK-Hep1 cells although no significant changes were induced by OPN-a. Consistently, OPN isoforms differentially activated migrationassociated signaling pathways such that OPN-a and -b increased the expression of urokinase type plasminogen activator and the phosphorylation of p42/p44 MAP kinase, but these pathways were not activated by OPN-c. Thus, the findings of the present study suggest that OPN splice variants differentially couple to signaling pathways to modulate the migratory property of HCC cells and that this is one of the mechanisms underlying the pathological heterogeneity of HCC progression.

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Aims:  The objective of this study was to investigate the ability of specific bacterial components of Lactobacillus plantarum KFCC11389P to induce anti‐inflammatory mediators in cell cultures of the murine macrophage cell line, RAW 264·7. Methods and Results:  The RAW 264·7 cells were stimulated with viable bacterial cells (VC), heat‐killed (HK) cells, cell walls (CW) or ultrafiltrates of metabolic products (UF). An increase in the levels of tumour necrosis factor (TNF)‐α was observed in VC, HK and CW, but this effect was much lower in UF. VC stimulated higher levels of interleukin (IL)‐6 releases as well as nitric oxide production than HK. In contrast, UF and its separated molecule, fraction 4, were much strong IL‐10 inducers. Fraction 4 (8·1 kDa), especially, inhibited the production of pro‐inflammatory cytokines, IL‐6 (89% decrease) and TNF‐α (55% decrease), in lipopolysaccharide (LPS)‐stimulated murine macrophages. Conclusions:  The results of this study indicate that metabolic products of Lact. plantarum KFCC11389P could influence the immune‐modulating activity via IL‐10, and pretreatment with this specific molecule could inhibit LPS‐induced release of IL‐6 and TNF‐α. Significance and Impact of the Study:  Our findings suggest that the specific molecules of Lact. plantarum KFCC11389P may be useful for the treatment of acute inflammatory responses such as Crohn’s disease or ulcerative colitis.