(−)-Epiafzelechin 5-O-βD-glucoside from crataeva religiosa

Epiafzelechin 5-glucoside was characterized from the bark of Crataeva religiosa together with other known compounds.     

Echinicola shivajiensis sp. nov., a novel bacterium of the family “Cyclobacteriaceae” isolated from brackish water pond

Strain AK12^T, an orange pigmented Gram-negative, rod shaped, non-motile bacterium, was isolated from a mud sample collected from a brackish water pond at Rampur of West Bengal, India. The strain was positive for oxidase, catalase and phosphatase. The predominant fatty acids were iso-C_15:0 (42.7%), iso-C_17:0 3OH (13.2%), C_16:1ω7c/C_16:1ω6c (summed feature 3) (8.0%), iso-C_17:1 I/anteiso-C_17:1 B (summed feature 4) (6.1%) and iso-C_17:1ω9c/C_16:0 10-methyl (summed feature 9) (9.4%). Strain AK12^T contained MK-7 as the major respiratory quinone and phosphatidylethanolamine, one unidentified aminophospholipid and six unidentified lipids as the polar lipids. The G + C content of DNA of the strain AK12^T was 46.2 mol%. The 16S rRNA gene sequence analysis indicated that strain AK12^T was member of the genus Echinicola and closely related to Echinicola vietnamensis, Echinicola pacifica and Echinicola jeungdonensis with pair-wise sequence similarity of 96.8, 96.3 and 96.0% respectively. Phylogenetic analyses indicated that the strain AK12^T clustered with E. vietnamensis and together with E. pacifica and E. jeungdonensis with a phylogenetic distance of 5.1, 6.3 and 6.6% (94.9, 93.7 and 93.4% similarity) respectively. Based on data from the current polyphasic study, strain AK12^T is proposed as a novel species of the genus Echinicola, for which the name Echinicola shivajiensis sp. nov. is proposed. The type strain of E. shivajiensis is AK12^T (= MTCC 11083^T = JCM 17847^T).     

The Effect of Motivation on Movement: A Study of Bradykinesia in Parkinson’s Disease

Background

Bradykinesia is a cardinal feature of Parkinson’s disease (PD). Despite its disabling impact, the precise cause of this symptom remains elusive. Recent thinking suggests that bradykinesia may be more than simply a manifestation of motor slowness, and may in part reflect a specific deficit in the operation of motivational vigour in the striatum. In this paper we test the hypothesis that movement time in PD can be modulated by the specific nature of the motivational salience of possible action-outcomes.

Methodology/Principal Findings

We developed a novel movement time paradigm involving winnable rewards and avoidable painful electrical stimuli. The faster the subjects performed an action the more likely they were to win money (in appetitive blocks) or to avoid a painful shock (in aversive blocks). We compared PD patients when OFF dopaminergic medication with controls. Our key finding is that PD patients OFF dopaminergic medication move faster to avoid aversive outcomes (painful electric shocks) than to reap rewarding outcomes (winning money) and, unlike controls, do not speed up in the current trial having failed to win money in the previous one. We also demonstrate that sensitivity to distracting stimuli is valence specific.

Conclusions/Significance

We suggest this pattern of results can be explained in terms of low dopamine levels in the Parkinsonian state leading to an insensitivity to appetitive outcomes, and thus an inability to modulate movement speed in the face of rewards. By comparison, sensitivity to aversive stimuli is relatively spared. Our findings point to a rarely described property of bradykinesia in PD, namely its selective regulation by everyday outcomes.     

RAD51 haploinsufficiency causes congenital mirror movements in humans

Congenital mirror movements (CMM) are characterized by involuntary movements of one side of the body that mirror intentional movements on the opposite side. CMM reflect dysfunctions and structural abnormalities of the motor network and are mainly inherited in an autosomal-dominant fashion. Recently, heterozygous mutations in DCC, the gene encoding the receptor for netrin 1 and involved in the guidance of developing axons toward the midline, have been identified but CMM are genetically heterogeneous. By combining genome-wide linkage analysis and exome sequencing, we identified heterozygous mutations introducing premature termination codons in RAD51 in two families with CMM. RAD51 mRNA was significantly downregulated in individuals with CMM resulting from the degradation of the mutated mRNA by nonsense-mediated decay. RAD51 was specifically present in the developing mouse cortex and, more particularly, in a subpopulation of corticospinal axons at the pyramidal decussation. The identification of mutations in RAD51, known for its key role in the repair of DNA double-strand breaks through homologous recombination, in individuals with CMM reveals a totally unexpected role of RAD51 in neurodevelopment. These findings open a new field of investigation for researchers attempting to unravel the molecular pathways underlying bimanual motor control in humans.     

High-pressure phase transition and thermoelastic properties of europium chalcogenides

The pressure-induced crystal properties of Eu chalcogenides were investigated using two different models: a modified charge-transfer potential model consisting of Coulomb screening due to the delocalization of the f electron of the rare earth atom, and modified by covalency and zero-point energy effects along with attractive and repulsive interactions; and a charge-transfer model that excluded the covalency and zero-point energy effects in the previous model. Both models were used to visualize the effect of covalency on the mechanism of interaction of the constituent atoms. Eu chalcogenides transform from the Fm3m to the Pm3m phase under the influence of sufficient pressure (P(T) = 39.52, 21.01, 14.31, and 10.58 GPa), and their equations of state indicated decreases in volume during this phase transition of 6.38, 12.32, 12.76, and 11.15%, respectively, for EuO, EuS, EuSe, and EuTe. The results obtained from the models were in good agreement with corresponding experimental data. The elastic constants and Debye temperatures were also computed at normal and high pressures. Both of the models were found to be capable of successfully explaining these properties.     

On the interaction of UV-B radiation (280–315 nm) with water stress in crop plants

Cowpea ( Vigna unguiculata L. Walp.) seedlings (3-day-old) were subjected to 4 kinds of experimental treatments: (1) control without exposure to any stress (−D-UV), (2) moderate water stress with no UV-B irradiation (+D-UV), (3) no water stress but to UV-B radiation (−D+UV). and (4)moderate water stress and exposure to UV-B (+D+UV). UV-B and drought stress in the combined form elicited beneficial effects on the morphological and growth characteristics, and a few additive inhibitory effects in some functional processes. An increase in the specific leaf weight (SLW) was observed in the combination of stresses, which could be a defence mechanism against UV-B. The combination of stresses promoted the synthesis of anthocyanins and phenolic compounds. The responses of plants to the combination of stresses indicate that during simultaneous exposure of plants to multiple stresses, one form of stress could minimize the damage by the other. The enhancement of superoxide dismutase (SOD) and catalase activities appear to serve as acclimation mechanisms to scavenge the toxic, free radicals of oxygen produced under stress conditions. However, the inhibition in nitrate metabolism was greater in the combined stresses than in either of the stresses imposed separately. The results of this study illustrate that the interaction of stresses during simultaneous multiple stress conditions brings out certain beneficial effects.     

Thiophilic-interaction chromatography of enzymatically active tissue prostate-specific antigen (T-PSA) and its modulation by zinc ions

Prostate-specific antigen (PSA) is a serine protease secreted both by normal prostate glandular epithelial cells and prostate cancer cells. We explored "thiophilic-interaction chromatography" (TIC) to isolate tissue prostate-specific antigen (T-PSA) from fresh human prostate cancer tissue harvested by radical prostatectomy for the purpose to characterize T-PSA for its enzymatic activity and sensitivity to zinc ions. We have shown, for the first time, that T-PSA has strong affinity for the thiophilic gel (T-gel). The average recovery of T-PSA from T-gel is over 87%. The presence of PSA in the column eluate was confirmed by ELISA and SDS/PAGE. Western blot developed with monoclonal antibody to PSA revealed that T-PSA was predominantly in the "free" form having a molecular weight of 33 kDa. Furthermore, T-PSA was found to be enzymatically active. T-PSA was found to be less enzymatically active as compared to seminal plasma PSA. The inhibition of enzymatic activity of both f-PSA and T-PSA over a wide range of concentrations of Zn(2+) ions (10nM to 50 microM) was comparable. In contrast, the enzymatic activity of chymotrypsin, another serine-protease, was affected differently. At higher concentrations of Zn(2+) (10 microM and higher) the enzymatic activity of chymotrypsin was inhibited, whereas, at lower concentrations of Zn(2+) (5 microM and lower), the enzymatic activity was enhanced.     

Cloning and heterologous expression of ectoine biosynthesis genes from Bacillus halodurans in Escherichia coli

The genes involved in the biosynthetic pathway of ectoine (2-methyl-1,4,5,6-tetrahydropyrimidine-4-carboxylic acid) from Bacillus halodurans were cloned as an operon and expressed in E. coli. Analysis of the deduced ectoine biosynthesis cluster amino acid sequence revealed that the ectoine operon contain 2,389 bp, encoded by three genes; ectA, ectB and ectC that encode proteins of 189, 427 and 129 amino acids with deduced molecular masses of 21,048, 47,120 and 14,797 Da respectively. Extracts of induced cells showed two bands at 41 kDa and 17 kDa, possibly corresponding to the products of the later two genes. However the expression of ectA gene could not be ascertained by SDS-PAGE. The activity of the ectA protein was confirmed by an acylation assay. The transgenic E. coli accumulated upto 4.6 mg ectoine/l culture. This is the first report of an engineered E. coli strain carrying the ectoine genes of the alkaliphilic bacterium, B. halodurans.     

The paramutagenic line niv-44 has a 5 kb insert, Tam 2, in the chalcone synthase gene of Antirrhinum majus

Summary Several alleles of the nivea locus of Antirrhinum majus, both stable and unstable, have been characterised genetically (Harrison and Carpenter 1973 a, b). In this work the niv-44 allele is characterised at the molecular level. It contains a 5kb insertion element, Tam 2, which has 14 base pair inverted repeats. There is a three base pair duplication at the target site, which is at the first intron-exon boundary of the chalcone synthase gene. Tam 2 homologous sequences are present in multiple copies in several A. majus lines, including niv-53, and most have at least a 2.9 kb sequence in common with the copy at the chalcone synthase gene. Possible reasons for the apparent stability of the niv-44 allele and molecular explanations for the role of this allele in paramutation in A. majus are discussed.Dedicated to Professor Georg Melchers to celebrate his 50-year association with the journal