Distribution of alginate oligomers in Catharanthus roseus and Wasabia japonica cells cultured in a medium containing alginate oligomers

Distribution of alginate oligomers (AO) which are endogenous elicitor-like substances, in cultured plant cells were investigated by using AO conjugated with monopotassium 7-amino-1,3-naphthalenedisulfonate (ANDS). When AO-ANDS was added at 0.5 g l^–1 to the Catharanthus roseus cell culture, it adhered to the cells as observed by fluorescence microscopy. Using protoplasts of C. roseus, AO-ANDS was found not only in the cell walls but also in the cell membrane and cytoplasm. When C. roseus was cultivated in a medium containing oligo-galacturonic acids, as an endogenous elicitor, this was also found in the cell wall, cell membrane and cytoplasm of C. roseus cells. Similar results were also obtained with Wasabia japonica cells.     

Detection of Corynebacterium kutscheri from the oral cavity of rats.

A simple and useful method for the detection of C. kutscheri from the oral cavity of living rats was devised. In 10 sacrificed rats from two naturally and subclinically infected conventional colonies, 10(4.28) or 10(3.84) CFU/ml C. kutscheri were isolated from upper incisor swab extractions, while 10(1.38) or 10(1.58) and < 10 or 10(1.56) CFU/ml from the upper soft palate and pharynx, respectively. In another survey with 26 living animals, which were reared on the same rack, organisms were detected from the upper incisor and gingival swabs in 15 of 26 rats (57.7%). The results were reproducible at a second survey 10 days later. No organisms were isolated from any sites of the orally negative rats. These results indicated that culture of swab specimens from the upper incisors and gingivae of incisors is useful for the detection of C. kutscheri infection in living rats.     

Isolation of microsatellite markers from the drepanosiphid aphid Tuberculatus quercicola (Homoptera,Aphididae)

We isolated five polymorphic microsatellite loci from the drepanosiphid aphid Tuberculatus quercicola (Matsumura) that is associated with the Daimyo oak, Quercus dentata Thunberg, using the magnetic particles method. The isolated loci were polymorphic, with four to 16 alleles in 40 aphids. Expected heterozygosities ranged from 0.4 to 0.82. These loci can be used to quantify seasonal changes in clonal diversity in the metapopulation and the extent of clonal mixing in the colonies.     

Heterologous production of a new lasso peptide brevunsin in <Emphasis Type="Italic">Sphingomonas subterranea</Emphasis>

A shuttle vector pHSG396Sp was constructed to perform gene expression using Sphingomonas subterranea as a host. A new lasso peptide biosynthetic gene cluster, derived from Brevundimonas diminuta, was amplified by PCR and integrated to afford a expression vector pHSG396Sp-12697L. The new lasso peptide brevunsin was successfully produced by S. subterranea, harboring the expression vector, with a high production yield (10.2 mg from 1 L culture). The chemical structure of brevunsin was established by NMR and MS/MS experiments. Based on the information obtained from the NOE experiment, the three-dimensional structure of brevunsin was determined, which indicated that brevunsin possessed a typical lasso structure. This expression vector system provides a new heterologous production method for unexplored lasso peptides that are encoded by bacterial genomes.     

Role of Curdlan Sulfate in the Binding of HIV-1 gp120 to CD4 Molecules and the Production of gp120-Mediated TNF-α

To clarify the mechanism by which curdlan sulfate (CRDS) inhibits human immunodeficiency virus (HIV)-1 infection, we examined its influence on the binding of gp120 to CD4 molecules on T cells and macrophages, as well as on the production of TNF-α by gp120-stimulated macrophages (which promotes HIV-1 replication). CRDS treatment of cells not only inhibited the binding of HIV-1 gp120 to CD4⁺ cells, but also inhibited TNF-α production induced by gp120. Inhibition of HIV-1 infection by CRDS may be related to these two actions.     

B chromosomes, translocation between B and autosomes, and C-heterochromatin polymorphism of the grasshopper Podisma sapporensis Shir. (Orthoptera, Acrididae) in Hokkaido, northern Japan.

Seven categories of B chromosomes found in the brachypterus grasshopper Podisma sapporensis from Hokkaido populations differ in structure, size, and C-band content. The interchange between B and one autosome from M3 and sporadically M7 was observed in most of the populations examined. Such an interaction between standard and non-standard chromosomal set provides an insight into the integration of supernumerary chromosome. In addition, C-heterochromatin polymorphism was also identified in male karyotypes in some populations. These facts indicate P. sapporensis is a highly polymorphic species from the cytogenetic point of view.     

Endogenous elicitor-like effects of alginate on physiological activities of plant cells

 The effects of alginate on the physiological activities of plant cells were studied. Addition of alginate oligomer (AO) to the suspension culture of Catharanthus roseus L. or Wasabia japonica cells promoted the production of antibiotic enzymes such as 5′-phosphodiesterase or chitinase respectively. Ajmalicine (a secondary metabolite) production by C. roseus CP3 cells was also promoted when AO was added to the suspension culture. On the basis of these results, we assumed that alginate is an elicitor-like substance. We therefore compared the effect of AO on C. roseus L. and W. japonica cells with those of chitosan oligomer (CO) and oligo-galacturonic acid (OGA), which are well known as an exogenous elicitor and endogenous elicitor respectively. The effects of various concentrations of AO, OGA, and CO on the physiological activities, membrane permeability and protoplast formation of C. roseus L. or W. japonica cells were investigated. AO and OGA showed similar physiological effects, which were quite different from those of CO. Since alginate appeared to have similar effects to galacturonic acid, we concluded that alginate acts as an endogenous elicitor. Both alginate and galacturonic acid are uronic acids, and we considered their structural similarity. The effects of esterification of the carboxylic groups of alginate by propylene oxide were also studied. The greater the degree of esterification, the less the secretion of 5′-phosphodiesterase. Hence we assumed that carboxylic groups have an important role in the initiation of the elicitation reaction in plant cells, as shown in the case of galacturonic acid. Received: 18 January 1999 / Received revision: 2 April 1999 / Accepted: 1 May 1999     

Metabolism of Some “Second”– and “Fourth”–Generation Antidepressants: Iprindole, Viloxazine, Bupropion, Mianserin, Maprotiline, Trazodone, Nefazodone, and Venlafaxine

1. This review summarizes the major known aspects of the metabolism of second-generation (iprindole, viloxazine, bupropion, mianserin, maprotiline, and trazodone) and fourth-generation (nefazodone and venlafaxine) antidepressants.2. Discussions about specific enzymes involved and about possible pharmacokinetic drug–drug interactions, particularly as they relate to cytochrome P450 enzymes, are provided.     

Heat Stress Modulates Both Anabolic and Catabolic Signaling Pathways Preventing Dexamethasone‐Induced Muscle Atrophy In Vitro

It is generally recognized that synthetic glucocorticoids induce skeletal muscle weakness, and endogenous glucocorticoid levels increase in patients with muscle atrophy. It is reported that heat stress attenuates glucocorticoid‐induced muscle atrophy; however, the mechanisms involved are unknown. Therefore, we examined the mechanisms underlying the effects of heat stress against glucocorticoid‐induced muscle atrophy using C2C12 myotubes in vitro, focusing on expression of key molecules and signaling pathways involved in regulating protein synthesis and degradation. The synthetic glucocorticoid dexamethasone decreased myotube diameter and protein content, and heat stress prevented the morphological and biochemical glucocorticoid effects. Heat stress also attenuated increases in mRNAs of regulated in development and DNA damage responses 1 (REDD1) and Kruppel‐like factor 15 (KLF15). Heat stress recovered the dexamethasone‐induced inhibition of PI3K/Akt signaling. These data suggest that changes in anabolic and catabolic signals are involved in heat stress‐induced protection against glucocorticoid‐induced muscle atrophy. These results have a potentially broad clinical impact because elevated glucocorticoid levels are implicated in a wide range of diseases associated with muscle wasting. J. Cell. Physiol. 232: 650–664, 2017. © 2016 The Authors. Journal of Cellular Physiology published by Wiley Periodicals, Inc.     

Essential role of the PSI–LHCII supercomplex in photosystem acclimation to light and/or heat conditions by state transitions

Light and temperature affect state transitions through changes in the plastoquinone (PQ) redox state in photosynthetic organisms. We demonstrated that light and/or heat treatment induced preferential photosystem (PS) I excitation by binding light-harvesting complex II (LHCII) proteins. The photosystem of wheat was in state 1 after dark overnight treatment, wherein PQ was oxidized and most of LHCII was not bound to PSI. At the onset of the light treatment [25 °C in the light (100 µmol photons m^?2 s^?1)], two major LHCIIs, Lhcb1 and Lhcb2 were phosphorylated, and the PSI–LHCII supercomplex formed within 5 min, which coincided with an increase in the PQ oxidation rate. Heat treatment at 40 °C of light-adapted wheat led to further LHCII protein phosphorylation of, resultant cyclic electron flow promotion, which was accompanied by ultrafast excitation of PSI and structural changes of thylakoid membranes, thereby protecting PSII from heat damage. These results suggest that LHCIIs are required for the functionality of wheat plant PSI, as it keeps PQ oxidized by regulating photochemical electron flow, thereby helping acclimation to environmental changes.