Determination of sequence and absolute configuration of peptide amino acids by HPLC-MS/CD-based detection of liberated N-terminus phenylthiohydantoin amino acids

We report a method for the simultaneous determination of the sequence and absolute configuration of peptide amino acids using a combination of Edman degradation and HPLC-MS/CD. Phenylthiohydantoin (PTH) derivatives of 20 pairs of standard d- and l-amino acids were synthesized by the Edman reaction. The CD spectra of the derivatives revealed that each pair of the PTH derivatives exhibited the absorption with opposite signs at around 270 nm. These standard PTH derivatives showed well-resolved resolution without interference from byproducts in the ion chromatogram and clear positive/negative CD absorptions when subjected on a reversed phase HPLC-MS system coupled with a CD-2095 HPLC detector. This method was applied for the detection of a synthetic pentapeptide and a natural depsipeptide (halicylindramide C). The sequence and configuration of the pentapeptide and up to eight residues of halicylindramide C were successfully analyzed by this method. The amino acid configuration of the pentapeptide was also determined successfully by subjecting its acid hydrolysates to the Edman reaction followed by HPLC-MS/CD.Y

Collismycin C from the Micronesian Marine Bacterium Streptomyces sp. MC025 Inhibits Staphylococcus aureus Biofilm Formation

Biofilm formation plays a critical role in antimicrobial resistance in Staphylococcus aureus. Here, we investigated the potential of crude extracts of 79 Micronesian marine microorganisms to inhibit S. aureus biofilm formation. An extract of Streptomyces sp. MC025 inhibited S. aureus biofilm formation. Bioactivity-guided isolation led to the isolation of a series of 2,2′-bipyridines: collismycin B (1), collismycin C (2), SF2738 D (3), SF2738 F (4), pyrisulfoxin A (5), and pyrisulfoxin B (6). Among these bipyridines, collismycin C (2) was found to be the most effective inhibitor of biofilm formation by methicillin-sensitive S. aureus and methicillin-resistant S. aureus (MRSA), and this compound inhibited MRSA biofilm formation by more than 90% at a concentration of 50 μg/mL. The antibiofilm activity of collismycin C was speculated to be related to iron acquisition and the presence and position of the hydroxyl group of 2,2′-bipyridines

Marine Microorganism-Derived Macrolactins Inhibit Inflammatory Mediator Effects in LPS-Induced Macrophage and Microglial Cells by Regulating BACH1 and HO-1/Nrf2 Signals through Inhibition of TLR4 Activation

Recently, many natural products with unique structure and promising pharmacological potential have been reported from marine-derived microorganisms. The macrolactin A (MA), 15-epi-dihydromacrolactin F (DMF) and macrolactin F (MF) were obtained from the culture broth extract of a marine sediment derived microorganism Bacillus sp. HC001. In this study, MA, DMF and MF inhibited the production and expression of proinflammatory mediators of inducible nitric oxide synthase (iNOS) and cyclooxygenase–2 (COX-2) in LPS-stimulated RAW264.7 and BV2 cells. Also, MA, DMF and MF exert anti-inflammatory effects through the expression of heme oxygenase (HO) -1, a stress-inducing enzyme that converts heme to carbon monoxide (CO), iron and biliberdine. Toll-like receptor 4 (TLR4) expressed by lipopolysaccharide (LPS) was inhibited by increased expression of HO-1 transcription factor Nrf2 and down regulation of BTB Domain And CNC Homolog 1 (BACH1), inhibited phosphorylation of Mitogen-activated protein kinase kinase kinase 7 (MAP3K7, TAK1) and nuclear factor kappaB (NF-κB). These results show that MA, DMF and MF effectively inhibited TLR4 by regulating BACH1 and HO-1/Nrf2 signals in LPS-stimulated RAW264.7 and BV2 cells, which suggests the possibility of use as an anti-inflammatory agent

Bromo-honaucin A inhibits osteoclastogenic differentiation in RAW 264.7 cells via Akt and ERK signaling pathways

Osteoclasts are unique bone remodeling cells derived from multinucleated myeloid progenitor cells. They play homeostatic vital roles in skeletal modeling and remodeling but also destroy bone masses in many pathological conditions such as osteoporosis and rheumatoid arthritis. Receptor activation of NF-κB ligand (RANKL) is essential to osteoclastogenesis. In this study, we investigated the effects of bromo-honaucin A (Br-H A) isolated from Leptolyngbya crossbyana (cyanobacterium). To investigate the mechanism of the inhibitory effect of Br-H A on osteoclastogenesis, we employed Br-H Ain RANKL-treated murine monocyte/macrophage RAW 264.7 cells for osteoclastic differentiation in-vitro. The inhibitory effects on in-vitro osteoclastogenesis was evaluated by counting the number of Tartarate resistant acid phospatase (TRAP) positive multinucleated cells and by measuring the expression level of osteoclast-specific genes like matrix metalloproteinase 9 (MMP9), cathepsin K (CATH K), GRB2-associated-binding protein 2 (GAB2), c-terminal myc kinase (C-MYC), C-terminal Src kinase (C-SRC) and Microphthalmia-associated transcription factor (MITF). Moreover, Br-H A blocked the resorbing capacity of RAW 264.7 cells on calcium phosphate-coated plates. Finally, Br-H A clearly decreased the expression of Akt and also decreased the activation of ERK. Thus, the study identifies Br-H A as potent inhibitor potentialin the treatment of diseases involving abnormal bone lysis such as osteoporosis, rheumatoid arthritis, and periodontal bone degradation

Rhamnellosides A and B, ω-Phenylpentaene Fatty Acid Amide Diglycosides from the Fruits of Rhamnella franguloides

Two new ω-phenylpentaene fatty acid amide diglycosides, rhamnellosides A (1) and B (2), were isolated from the fruits of Rhamnella franguloides (Rhamnaceae). These compounds were prioritized using LC-MS/MS molecular networking dereplication based on our previous discovery of 2-acetoxy-ω-phenylpentaene fatty acid triglycosides berchemiosides A−C from a phylogenetically related species, Berchemia berchemiifolia. The structures of the isolated compounds were elucidated by spectroscopic analyses in combination with chemical derivatization. The pentaene groups of 1 and 2 were found to have (6E, 8E, 10Z, 12Z, 14E)-geometry, which is the same as that found in berchemioside A

Probiotics mixture increases butyrate, and subsequently rescues the nigral dopaminergic neurons from MPTP and rotenone-induced neurotoxicity

Microbiota in the gut affect brain physiology via various pathways, and dysbiosis seems to play a role in the pathogenesis of Parkinson's disease (PD). Probiotics showed pleiotropic effects on functions of the central nervous system via microbiota-gut-brain axis. However, no studies displayed the neuroprotective effects of probiotics in the Parkinson's disease. This study aimed to test the neuroprotective effects of probiotics in two different models of PD. We evaluated neuroprotective effects of a probiotic cocktail containing Lactobacillus rhamnosus GG, Bifidobacterium animalis lactis, and Lactobacillus acidophilus in PD models induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or rotenone utilizing behavioral tests, immunohistochemistry and neurochemical analysis. To assure the neuroprotection came from increased production of butyrate, we further determined beneficial effects of butyrate in the MPTP-mediated PD model. The probiotic mixture overtly protected the dopaminergic neurons against MPTP neurotoxicity. However, the probiotics downregulated expression of monoamine oxidase (MAO) B in the striatum, which was accompanied by a lower level of 1-methyl-4-phenylpyridinium (MPP ), the main neurotoxic metabolite of MPTP. Thus, we extended the investigation into the rotenone-induced PD model. Rescuing effects of the probiotics were observed in the setup, which came with increased levels of neurotrophic factors and butyrate in the brain. Lactobacillus rhamnosus GG was identified to be a major contributor to the induction of neurotrophic factors and downregulation of MAO B. Finally, we demonstrated that sodium butyrate attenuated MPTP-induced neuronal loss in the nigrostriatal pathway. Probiotics could ameliorate neurodegeneration at least partially by increasing butyrate level. These data highlight the role of probiotics for brain health, and their potential as a preventive measure for neurodegenerative diseases such as PD

Leveraging Children's Behavioral Distribution and Singularities in New Interactive Environments: Study in Kindergarten Field Trips

The behavior observations on young children in new, first-in-the-life environments have significant implications. We can often uniquely observe a child’s unforeseen interaction with the environment and peer-children. It would be not only a piece of discovery but a beginning of an open quest worth exploring. Out-of-classroom activities like kindergarten’s field trips are perfect opportunities, but those are quite different from regular classroom activities where the teachers’ conventional observation methods are hardly practical. This paper proposes a novel approach to extend the teachers’ awareness on the children’s field trip behaviors by means of mobile and sensor technology. We adopt the notion of behavioral distribution and singularities. We estimate the children’s representative behavioral state in a given context, and study the effect of focusing on the behaviors which are unlikely in this context. We discuss our 14-month collaborative study and various qualitative benefits through multiple deployments on actual kindergarten field trips.

4-(Hydroxymethyl)catechol Extracted From Fungi in Marine Sponges Attenuates Rheumatoid Arthritis by Inhibiting PI3K/Akt/NF-κB Signaling

Rheumatoid arthritis (RA) is a progressive autoimmune disease specific to synovial joints; it causes joint damage and other systemic abnormalities, thereby leading to physical disability and early mortality. Marine sponge-derived fungi, Pestalotiopsis sp., secrete immunosuppressive compounds in the culture broth. In the present study, we isolated 4-(hydroxymethyl)catechol (4-HMC) from these fungal species, and evaluated its anti-RA effects using a murine collagen-induced arthritis model and tumor necrosis factor-α-stimulated human RA synovial fibroblasts. Oral 4-HMC administration decreased the clinical arthritis score, paw thickness, histologic and radiologic changes, and serum IgG1 and IgG2a levels. It prevented the proliferation of helper T (Th) 1/Th17 CD4+ lymphocytes isolated from inguinal lymph nodes, thereby reducing inflammatory cytokine production in CIA mice. It decreased the expression of inflammatory mediators, including cytokines and matrix metalloproteinases (MMPs), both in vitro and in vivo. We observed that 4-HMC suppresses Th immune responses and MMP expression to inhibit inflammatory cytokine production in human RA synovial fibroblasts by modulating the PI3K/Akt/NF-κB pathway. These results verify the anti-RA potential of 4-HMC