Minor proteins,mobile arms and membrane-capsid interactions in the bacteriophage PRD1 capsid

Bacteriophage PRD1 shares many structural and functional similarities with adenovirus. A major difference is the PRD1 internal membrane, which acts in concert with vertex proteins to translocate the phage genome into the host. Multiresolution models of the PRD1 capsid, together with genetic analyses, provide fine details of the molecular interactions associated with particle stability and membrane dynamics. The N- and C-termini of the major coat protein (P3), which are required for capsid assembly, act as conformational switches bridging capsid to membrane and linking P3 trimers. Electrostatic P3-membrane interactions increase virion stability upon DNA packaging. Newly revealed proteins suggest how the metastable vertex works and how the capsid edges are stabilized.     

Dynamics of the changes in homogenate respiratory activity after rat whole liver storage at 4 degrees C

Homogenate respiratory activity was studied after different storage terms of the whole rat liver at 4 degrees C in sucrose-based solution and following normothermic reperfusion. Preservation of homogenate respiratory activity in all metabolic states after normothermic reperfusion of the control liver (60 min, 4 degrees C) is shown. Further storage (6 and 24 hrs) of isolated liver under the mentioned above conditions strengthens the substrate respiration of homogenate both after storage and after normothermic reperfusion. At the same time oxidative phosphorylation does not practically change. No change was noted in respiratory activity in the states 3, 4ADP and 3DNP after 24 hrs of liver storage in respect of a previous term. Following normothermic liver reperfusion contributes to a statistically true reduction of mentioned parameters of respiration, that correlates with a decrease in the degree of respiration and phosphorylation coupled of the studied system.     

Patterns of polymorphism detected in the chloroplast and nuclear genomes of barley landraces sampled from Syria and Jordan

In order to examine how molecular polymorphism in barley landraces, sampled from five different ecogeographical regions of Syria and Jordan, is organised and partitioned, genetic variability at 21 nuclear and 10 chloroplast microsatellite loci were examined. Chloroplast polymorphism was detected, with most variation being ascribed to differences between the five regions (F_st 0.45) and to within sites within each region (F_st 0.44). Moreover, the distribution of chloroplast polymorphism is structured and not distributed randomly across the barley landraces sampled. From a total of 125 landrace accessions (five lines from each of five sites from each of five regions) genotyped with 21 SSRs a total of 244 alleles were detected, of which 38 were common to the five regions sampled. Most nuclear variation was detected within sites. Significant differentiation between sites (F_st 0.29) was detected with nuclear SSRs and this partially mirrored polymorphism in the chloroplast genome. Strong statistical associations/interaction was also detected between the chloroplast and nuclear SSRs, together with non-random association (linkage disequilibrium) of alleles at both linked and unlinked SSR loci. These results are discussed in the context of adaptation of landraces to the extreme environment, the concept of 'adapted gene complexes' and the exploitation of landraces in breeding programmes.Communicated by P. Langridge     

Determination of in situ bacterial growth rates in aquifers and aquifer sediments

Laboratory and field-scale studies with stained cells were performed to monitor cell growth in groundwater systems. During cell division, the fluorescence intensity of the protein stain 5-(and 6-)-carboxyfluorescein diacetate succinimidyl ester (CFDA/SE) for each cell is halved, and the intensity can be tracked with a flow cytometer. Two strains of bacteria, Comamonas sp. strain DA001 and Acidovorax sp. strain OY-107, both isolated from a shallow aquifer, were utilized in this study. The change in the average generation or the average fluorescence intensity of the CFDA/SE-stained cells could be used to obtain estimates of doubling times. In microcosm experiments, the CFDA/SE-based doubling times were similar to the values calculated by total cell counting and were independent of cell concentration. Intact and repacked sediment core experiments with the same bacteria indicated that changes in groundwater chemistry were just as important as growth rates in determining planktonic cell concentrations. The growth rates within the sediment cores were similar to those calculated in microcosm experiments, and preferential transport of the daughter cells was not observed. The experiments indicated that the growth rates could be determined in systems with cell losses due to other phenomena, such as attachment to sediment or predation. Application of this growth rate estimation method to data from a field-scale bacterial transport experiment indicated that the doubling time was approximately 15 days, which is the first known direct determination of an in situ growth rate for bacteria in an aquifer.     

Synthesis and energy transfer efficiency of FRET terminators derived from different linkers

A number of different energy transfer dye labeled-cassettes were synthesized using aminoacid based trifunctional linkers and coupled to the propargylamino-substituted dideoxynucleoside-5'-triphosphates (ddNTPs). These terminators were evaluated for their energy transfer efficiency and DNA sequencing potential using thermostable DNA polymerase.     

Energy status of isolated hepatocytes after long-term cold storage in various types of media

Using of isolated hepatocytes for investigation of the effects of hypothermia, it has been demonstrated that sucrose-base solution provides of maintenance of the energetic parameters (level of ATP, glucose synthesis, rate of gluconeogenesis) within 48 hrs of storage at 4 degrees C. It efficiency was compared with effect on the energetic status of isolated hepatocytes widely used preservation solution--solution of University Wisconsin (UW). After long-term of cold storage of isolated hepatocytes (72 hrs) at 4 degrees C in both solutions, it has been shown sharp decrease of ATP level (on two time). Viability of the liver cells (in both cases) was practically without change.     

Changes in paroxysmal brainwave patterns of epileptics by weak-field magnetic stimulation

In order to assess the effects of weak-field magnetic stimulation on brain electrical activity in epileptics, three patients suffering from mesial temporal lobe epilepsy (MTLE) were exposed to DC magnetic fields of 0.9 and 1.8 millitesla (mT). The EEG activity was recorded simultaneously from intracranial electrodes inserted through the foramen ovale (FO) and scalp electrodes. Significant enhancement of interictal epileptiform activity was observed in two patients, while in one patient, magnetic stimulation resulted in the cessation of interictal spike/wave trains.