Bacteria immobilised in Gels: Improved methodologies for antifouling and biocontrol applications

A range of bacteria, including the marine bacterium Pseudoalteromonas tunicata which produces antifouling compounds, and Escherichia coli were used to investigate methods for immobilising bacteria in gels. Different types of matrices were screened using the survival of barnacle nauplii as a bioassay. A Dupont? polyvinylalcohol (PVOH) 10% gel was found to be the optimal matrix. This non-toxic gel remained stable in seawater while allowing for an outflux of active biological compounds from the bacterial cells. The presence of active bacterial cells in the matrix was tested by CTC-staining, green fluorescent protein (GFP) expressing bacteria and a barnacle larvae bioassay. The Dupont? PVOH 10% gels containing P. tunicata cells were inhibitory against larvae for a period of up to 2 weeks. In further studies using gels containing immobilised bacteria, the E. coli strain C600 was employed based on its cell size, stress resistance and the fact that a plasmid for the expression of GFP could be transferred and maintained in the cells. Immobilised E. Coli cells maintained their viability in the Dupont? PVOH 10% gels for as long as 2 months, and the life-span of these "biologically active"; gels was increased to more than 2 months by the incorporation of small beads into the gels. The results indicate that bacteria can be immobilised in coatings for periods of time consistent with the needs of some antifouling and antibacterial applications.     

Effects of abscisic Acid treatment on the thermostability of the photosynthetic apparatus in barley chloroplasts

Thermostability of the photosynthetic apparatus of abscisic acid (ABA)-treated seedlings of barley (Hordeum vulgare) was studied by light-scattering and by fluorescence measurements of isolated chloroplasts. ABA treatment markedly decreased heat damage of the chloroplast ultrastructure; an exogenous ABA concentration of 10⁻⁵ molar was most effective. Heat-induced increase of the 77 kilodalton fluorescence ratio F₇₄₀/F₆₈₅ was also smaller at this ABA concentration. The heat-induced increase of the initial chlorophyll fluorescence level (F_o) was virtually eliminated in ABA-treated (10⁻⁵ molar) chloroplasts up to 45°C and slightly increased at 50°C, relative to control chloroplasts where F_o increased even at 35°C and reached its maximal value at 45°C. In control chloroplasts, F_o increased with a 5-minute pretreatment temperature, an effect observed as low as 35°C. F_o was maximal at 45°C. In contrast, chloroplasts treated with 10⁻⁵ molar ABA did not exhibit a heat-induced increase in F_o until 50°C.     

The symptomless leaf infection with grapevine leafroll associated virus 3 in grown in vitro plants as a simple model system for investigation of viral effects on photosynthesis

The photosynthetic changes evaluated by oxygen evolution, chlorophyll fluorescence, photoacoustics, and delayed fluorescence (DF) were studied in leaves of grown in vitro for 8 weeks grapevine plants (Vitis vinifera) infected by grapevine leafroll-associated virus 3 (GLRaV-3). The infected leaves were characterized during the viral infection without visible disease symptoms. The symptomless infection led to a decrease in plant biomass. The non-photochemical fluorescence quenching, qN, declined, whereas the photochemical quenching, qP, and the Chl a/b ratio were not significantly affected. Photoacoustic and oxygen evolution measurements showed that the energy storage and oxygen evolution rate decreased in the infected leaves. Enhanced alternative electron sinks during the symptomless viral infection were also estimated. The changes in fluorescence and DF temperature curves demonstrated an enhanced stability of the thylakoid membranes in the infected leaves. This effect was clearly expressed at high actinic light intensities. The viral infected in vitro grown grapevine plants were used in the present study as a simplified model system that allow to avoid the involvement of different environmental factors that could interfere with the GLRaV infection and the virus-grapevine interactions. Thus, the 'pure' impact of the viral infection on photosynthesis could be investigated.     

Collapsin Response Mediator Protein-2: An Emerging Pathologic Feature and Therapeutic Target for Neurodisease Indications

Collapsin response mediator protein-2 (DPYSL2 or CRMP2) is a multifunctional adaptor protein within the central nervous system. In the developing brain or cell cultures, CRMP2 performs structural and regulatory functions related to cytoskeletal dynamics, vesicle trafficking and synaptic physiology whereas CRMP2 functions in adult brain are still being elucidated. CRMP2 has been associated with several neuropathologic or psychiatric conditions including Alzheimer’s disease (AD) and schizophrenia, either at the level of genetic polymorphisms; protein expression; post-translational modifications; or protein/protein interactions. In AD, CRMP2 is phosphorylated by glycogen synthase kinase-3β (GSK3β) and cyclin dependent protein kinase-5 (CDK5), the same kinases that act on tau protein in generating neurofibrillary tangles (NFTs). Phosphorylated CRMP2 collects in NFTs in association with the synaptic structure-regulating SRA1/WAVE1 (specifically Rac1-associated protein-1/WASP family verprolin-homologous protein-1) complex. This phenomenon could plausibly contribute to deficits in neural and synaptic structure that have been well documented in AD. This review discusses the essential biology of CRMP2 in the context of nascent data implicating CRMP2 perturbations as either a correlate of, or plausible contributor to, diverse neuropathologies. A discussion is made of recent findings that the atypical antidepressant tianeptine increases CRMP2 expression, whereas other, neuroactive small molecules including the epilepsy drug lacosamide and the natural brain metabolite lanthionine ketimine appear to bind CRMP2 directly with concomitant affects on neural structure. These findings constitute proofs-of-concept that pharmacological manipulation of CRMP2 is possible and hence, may offer new opportunities for therapy development against certain neurological diseases.     

Effect of Moringa oleifera leaves on hematological profile of fluorosis affected rats

Fluorosis is a metabolic disease that is endemic in nearly 25 countries with India being one of the most affected. It primarily affects the bone and the teeth. Moringa oleifera (MO) leaves are known to reduce the effect of fluorosis on various tissues. Therefore, it is of interest to document the effect of Moringa oleifera leaves on the hematological profile of fluorosis affected rats. Twenty four Sprague Dawley rats were housed two per cage in a room with 12 hours light and 12 hours dark cycle. The rats were allowed to adjust to the laboratory environment for about one to two weeks before the beginning of the study. This study reveals that MO leaves is effective in reducing the plasma fluoride content. It also helps in improving the Hb % and RBC count in fluorosis affected rats. Data shows that Moringa olifera leaves powder is effective in reducing the plasma fluoride content. It also helps in improving the Hemoglobin percentage & Red Blood Cell count in fluorosis affected rats.     

Oxidized LDLs affect nitric oxide and radical generation in brain endothelial cells

There is an increase in the generation of reactive oxygen species and nitric oxide in the cerebral microcirculation in Alzheimer's disease. The factors that cause this increase in oxidative stress have not been identified. Increasing evidence suggests that there are common mechanisms in atherosclerosis and Alzheimer's disease. The objective of this study was to determine the effects of oxidized low density lipoproteins (LDLs) on brain endothelial cells. Cultured rat brain endothelial cells were treated with either native LDL (10 microg/ml) or LDL oxidized in vitro using 4-hydroxy-2-nonenal (HNE-LDL) (10 microg/ml), for 24h. The results showed that HNE-LDL significantly increased production of nitric oxide (p<0.01), decreased membrane fluidity (p<0.05), and increased reactive oxygen species generation (p<0.01). These data demonstrate that oxidized LDLs affect nitric oxide and radical generation in brain endothelial cells and could contribute to cerebrovascular dysfunction in Alzheimer's disease.     

Development of a biotechnological procedure for treatment of animal wastes to obtain inexpensive biofertilizer

A biotechnological procedure based on alkaline hydrolysis has been developed for effective processing of various types industrial animal wastes to convert them into a low cost high value biodegradable end product. It was demonstrated in laboratory scale experiments that the bioproduct obtained positively influenced microbial soil populations and ryegrass growth in both soils used, park soil and mine spoils. As the remaining partially degraded waste residue is highly dispersed it should act as a slow release fertilizer, thus feeding plants additionally. Therefore, the protein hydrolysate obtained is suitable for application as a harmless and valuable biofertilizer. The proposed method for solubilization of proteinaceous wastes is simple and economically viable making its implementation easier on an industrial scale. Therefore, the method could be of great help to the enterprises of the meat industry, avoiding using landfills and incineration.     

Secondary metabolites of Ceratophyllum demersum

Ceratophyllum demersum L. is abundant in European rivers and ponds and produces a large amount of biomass. Almost nothing is known about its secondary metabolites. We isolated two flavonoid glycosides and identified one of them an apigenin-7-O-glucoside. Seven sterols, the main one sitosterol, were also identified. Volatile compounds contained mainly n-paraffins, together with benzyl acetate and a sesquiterpene.     

Modeling study of the influences of the aromatic transitions and the local environment on the far-UV rotational strengths in TEM-1 β-lactamase

Rotational strengths in the far-UV of TEM-1 β-lactamase have been investigated with two theoretical models based on the matrix method. The first model excludes, and a second includes, effects of the local electrostatic interactions on the chromophore energies. Special attention is given to the contributions of the aromatic side-chain chromophores, and the mechanisms of generation of rotational strengths are analyzed. The sensitivity of the computational models with respect to the structural changes of the protein are discussed. Figure Structure of TEM-1 β-lactamase. Both domains—α and αβ, the secondary structural elements and the aromatic and disulfide chromophores are shown