Analysis of the nucleotide context of Arabidopsis thaliana mitochondrial mRNA editing sites

We have studied the effects of 1 mM solutions of L-amino acids on the X-ray- and heat-induced generation of hydrogen peroxide and hydroxyl radicals in phosphate buffer (5 mM, pH 7.4). Hydrogen peroxide was estimated by enhanced chemiluminescence in the luminol/p-iodophenol/peroxidase system; hydroxyl radicals were detected with a fluorescent probe coumarin-3-carboxylic acid. We demonstrate that amino acids can be grouped into three categories by their effect on X-ray-induced H₂O₂ production: those that reduce, increase, and have no influence on H₂O₂ yield. Similar amino acid effects were observed upon heating; however, the composition of respective amino acid groups was different. All amino acids lowered the X-ray-induced hydroxyl radical production, and the most effective were Cys > His > Phe = Met = Trp > > Tyr (in descending order). Hydroxyl radical generation induced by heating was inhibited by Met, His, and Phe; enhanced by Ser; and not affected by Tyr and Pro. Thus, amino acids have different effects on the production of reactive oxygen species by X-rays and heating, and some amino acids appear to be effective natural antioxidants.     

Effect of Ca<Superscript>2+</Superscript> and cAMP on protein phosphorylation in mitochondria of maize seedlings

The effect of common intracellular signals (Ca²⁺ and cAMP) on the activity of protein phosphorylation in mitochondria was investigated in coleoptiles of maize (Zea mays L.). Treatment of isolated mitochondria with 2 mM CaCl₂ brought about an increase in the level of phosphorylation of proteins with mol ws of 74, 60, and 33 kD but considerably reduced phosphorylation of the protein with a mol wt of 51.5 kD. In the presence of Ca²⁺, phosphorylation of polypeptides with mol wts of 59 and 66 kD was also detected. cAMP considerably reduced phosphorylation of essentially all the investigated proteins in isolated mitochondria, which could be explained by activation of their dephosphorylation. Phosphorylation of mitochondrial proteins involves a polypeptide of about 94 kD showing kinase activity, which may be proper protein kinase or one of the subunits of a compound structure. In maize mitochondria, PP1A phosphatases were found. A hypothesis was advanced that redox-dependent phosphorylation/dephosphorylation of mitochondrial proteins plays an important role in mitochondrial signaling in higher plants.     

Analysis of 16S rDNA reveals bacterial shift during in vitro fermentation of fermentable carbohydrate using piglet faeces as inoculum

In vitro fermentation of sugar beet pulp (SBP) was carried out to determine which bacterial species would be enriched by use of this carbohydrate source. Faeces from four weaning piglets as a source of inoculum was also compared. The microbial diversity of the prominent bacteria before and after this in vitro fermentation was analysed using denaturing gradient gel electrophoresis (DGGE) of PCR amplicons of 16S rDNA. Before fermentation, the DGGE profiles showed differences between cultures inoculated with faeces from different piglets, though some bands were common to all piglets. After fermentation of SBP, three dominant bands appeared, of which two bands appeared in all samples and one for both replicates of one piglet. Sequences of the corresponding 16S rDNA of two bands showed 92% similarity to Eubacterium eligens and 96% similarity to Lachnospira pectinoschiza, and that of the third band 95% to L. pectinoschiza.     

The CELO-ANG recombinant avian adenovirus with human angiogenine gene inducing neovascularization in the anterior tibial muscle of rat

The CELO recombinant avian adenovirus carrying the gene coding the human angiogenine (ANG) synthesis was obtained. Expression of the angiogenine gene was shown in the LMH cell culture after infection with the CELO-ANG virus. The ability of CELO recombinant adenoviruses to carry out the delivery and expression of alien genes in muscle cells was demonstrated in experiments with laboratory animals (Wistar line rats). The induced neovascularization in rat muscles after the animals were administered the CELO-ANG viruses was shown.     

First record of leaf-hole shelters used and modified by leaf beetles (Coleoptera,Chrysomelidae), with descriptions of two new Orthaltica Crotch species from?southern India

Behavioural novelties observed in adult leaf beetles of two new Orthaltica Crotch species include: 1) the use of low cost leaf-hole shelters, either in pre-formed holes produced by larger beetles that fed on the same leaf, or artificially created holes as part of an experiment; and 2) the use of faeces to partition the hole. Two new southern Indian species of the genus Orthaltica are described and illustrated: Orthaltica syzygium and Orthaltica terminalia. Host plants are identified for both species. A key to the Indian species of Orthaltica is provided.     

A revision of the Early Carnian Trachyceratidae (Ammonoidea) of Northeastern Asia

Major morphological features of the shell are studied, and new trachyceratid genera, Boreotrachyceras gen. nov. with the type species B. omkutchanicum (Bytschkov) and Okhototrachyceras gen. nov. with the type species O. seimkanense (Bytschkov), are established based on material from the Lower Carnian of the Omolon Massif and Northern Okhotsk Region. The first record of the genus Trachyceras in the Boreal Realm allows the correlation of the omkutchanicum Zone of Northeastern Asia with the standard aon Zone.