ALBERT

Beschreibung: Trehalose-6-phosphate phosphatase (TPP) catalyzes the final step in the biosynthesis of the anti-stress sugar trehalose. An 82 kDa TPP enzyme was isolated from Candida utilis with 61% yield and 43-fold purification. The protein sequence, determined by N-terminal sequencing and MALDI-TOF analysis, showed significant homology with known TPP sequences from related organisms. The full length gene sequence of TPP of Candida utilis was identified using rapid amplification of cDNA ends - PCR reaction (RACE-PCR). The gene was cloned and expressed in E. coli BL21. Recombinant TPP enzyme was isolated using affinity chromatography. CD spectroscopy and steady state fluorescence revealed that the structural and conformational aspects were identical in both native and recombinant forms. The biochemical properties of the two forms were also similar. K m was determined to be ∼0.8 mM. Optimum temperature and pH was found to be 30 °C and 8.5 respectively. Activity was dependent on the presence of divalent cations and inhibited by metal chelators. Methylation mediated regulation of TPP enzyme and its effect on the overall survival of the organism under stress were investigated. The results indicated that enhancement of TPP activity by methylation at the Cysteine residues increased resistance of Candida cells against thermal stress. This work involves extensive investigations towards understanding the physico-chemical properties of the first TPP enzyme from any yeast strain. The mechanism by which methylation regulates its activity has also been studied. A correlation between regulation of trehalose synthesis and survivability of the organism under thermal stress was established. J. Cell. Physiol. 9999: XX–XX, 2014. © 2014 Wiley Periodicals, Inc.

Beschreibung: [1]  Structural evolution of monsoon clouds in the core monsoon region of India has been examined using multi-sensor data. Invigoration of warm clouds above 4.5 km (occurring in only 15.4% days of the last 11 monsoon seasons) is associated with a transition from negative to positive normalized rainfall anomaly. Cloud top pressure reduces with an increase in aerosol optical depth at a higher rate of invigoration in drier condition (characterized by large fraction of absorbing aerosols) than wet condition. Cloud effective radius for warm clouds does not show any significant change with an increase in aerosol concentration in presence of high liquid water path, probably due to strong buffering role of meteorology. The structural evolution of monsoon clouds is influenced by both dynamic and microphysical processes that prolong the cloud lifetime, resulting in infrequent rainfall. Our results call for improved representation of aerosol and cloud vertical structures in the climate models to resolve this issue.

Beschreibung: Background: A novel herbal formulation LI10903F, alternatively known as LOWAT was developed based on its ability to inhibit adipogenesis and lipogenesis in 3T3-L1 adipocytes model. The clinical efficacy and tolerability of LI10903F were evaluated in an eight-week, randomized, double-blind, placebo-controlled, clinical trial in 50 human subjects with body mass index (BMI) between 30 and 40 kg/m2 (clinical trial registration number: ISRCTN37381706). Participants were randomly assigned to either a placebo or LI10903F group. Subjects in the LI10903F group received 300 mg of herbal formulation thrice daily, while subjects in the placebo group received 300 mg of placebo capsules thrice daily. All subjects were provided a standard diet (2,000 kcal daily) and participated in a moderate exercise of 30 min walk for five days a week. Additionally, the safety of this herbal formulation was evaluated by a series of acute, sub-acute toxicity and genotoxicity studies in animals and cellular models. Results: After eight weeks of supplementation, statistically significant net reductions in body weight (2.49 kg; p=0.00005) and BMI (0.96 kg/m2; p=0.00004) were observed in the LI10903F group versus placebo group. Additionally, significant increase in serum adiponectin concentration (p=0.0076) and significant decrease in serum ghrelin concentration (p=0.0066) were found in LI10903F group compared to placebo group. Adverse events were mild and were equally distributed between the two groups. Interestingly, LI10903F showed broad spectrum safety in a series of acute, sub-acute toxicity and genotoxicity studies. Conclusions: Results from the current research suggest that LI10903F or LOWAT is well-tolerated, safe and effective for weight management.

Beschreibung: Pointillistic based super-resolution techniques, such as photoactivated localization microscopy (PALM), involve multiple cycles of sequential activation, imaging, and precise localization of single fluorescent molecules. A super-resolution image, having nanoscopic structural information, is then constructed by compiling all the image sequences. Because the final image resolution is determined by the localization precision of detected single molecules and their density, accurate image reconstruction requires imaging of biological structures labeled with fluorescent molecules at high density. In such image datasets, stochastic variations in photon emission and intervening dark states lead to uncertainties in identification of single molecules. This, in turn, prevents the proper utilization of the wealth of information on molecular distribution and quantity. A recent strategy for overcoming this problem is pair-correlation analysis applied to PALM. Using rigorous statistical algorithms to estimate the number of detected proteins, this approach allows the spatial organization of molecules to be quantitatively described.

Beschreibung: The effect of upwelling events, storm water discharge, and local circulation on phytoplankton blooms in the central California and Southern California Bight (SCB) coastal zones was analyzed using 10+ years (1997–2007) of remotely sensed surface chlorophyll concentration (CHL, derived from SeaWiFS ocean color), sea surface temperature, and modeled freshwater discharge. Analysis of variability and factors associated with phytoplankton blooms was conducted using the offshore extension of zones of CHL 〉 5 mg m−3; this method excludes terrestrial interference that complicates the use of ocean color to investigate phytoplankton blooms in coastal waters. In the SCB, blooms were most frequent in spring and associated with the spring transition to an upwelling regime. Along the Central Coast, blooms persisted from spring to autumn during seasonal intensification of upwelling. Offshore CHL extensions showed a significant positive trend during 1997–2007, with maxima in 2000–2001 and 2005–2006 that coincided with higher than normal frequency of upwelling events. Upwelling was found to be a major factor driving phytoplankton blooms, although the standard upwelling index derived from large-scale atmospheric circulation was decoupled from the frequencies of both upwelling events and phytoplankton blooms. Areas of longer residence time associated with natural boundaries between coastal ocean regions had more extensive and persistent blooms. The influence of storm water discharge on offshore CHL extension appeared to be limited to areas in close proximity to major river mouths. These “hot spots” were also co-located with ocean outfalls of Publicly Owned Treatment Works (POTW) discharge and, in some cases, longer residence time of coastal waters.

Beschreibung: Background: The three-dimensional structure of a protein can be described as a graph where nodes represent residues andthe strength of non-covalent interactions between them are edges. These protein contact networks can beseparated into long and short-range interactions networks depending on the positions of amino acids inprimary structure. Long-range interactions play a distinct role in determining the tertiary structure of aprotein while short-range interactions could largely contribute to the secondary structure formations. Inaddition, physico chemical properties and the linear arrangement of amino acids of the primary structure ofa protein determines its three dimensional structure. Here, we present an extensive analysis of proteincontact subnetworks based on the London van der Waals interactions of amino acids at different lengthscales. We further subdivided those networks in hydrophobic, hydrophilic and charged residues networksand have tried to correlate their influence in the overall topology and organization of a protein. Results: The largest connected component (LCC) of long (LRN)-, short (SRN)- and all-range (ARN) networks withinproteins exhibit a transition behaviour when plotted against different interaction strengths of edges amongamino acid nodes. While short-range networks having chain like structures exhibit highly cooperativetransition; long- and all-range networks, which are more similar to each other, have non-chain like structuresand show less cooperativity. Further, the hydrophobic residues subnetworks in long- and all-range networkshave similar transition behaviours with all residues all-range networks, but the hydrophilic and chargedresidues networks don't. While the nature of transitions of LCC's sizes is same in SRNs for thermophilesand mesophiles, there exists a clear difference in LRNs. The presence of larger size of interconnectedlong-range interactions in thermophiles than mesophiles, even at higher interaction strength between aminoacids, give extra stability to the tertiary structure of the thermophiles. All the subnetworks at different lengthscales (ARNs, LRNs and SRNs) show assortativity mixing property of their participating amino acids.While there exists a significant higher percentage of hydrophobic subclusters over others in ARNs andLRNs; we do not find the assortative mixing behaviour of any the subclusters in SRNs. The clusteringcoefficient of hydrophobic subclusters in long-range network is the highest among types of subnetworks.There exist highly cliquish hydrophobic nodes followed by charged nodes in LRNs and ARNs; on the otherhand, we observe the highest dominance of charged residues cliques in short-range networks. Studies on theperimeter of the cliques also show higher occurrences of hydrophobic and charged residues' cliques. Conclusions: The simple framework of protein contact networks and their subnetworks based on London van der Waalsforce is able to capture several known properties of protein structure as well as can unravel several newfeatures. The thermophiles do not only have the higher number of long-range interactions; they also havelarger cluster of connected residues at higher interaction strengths among amino acids, than their mesophiliccounterparts. It can reestablish the significant role of long-range hydrophobic clusters in protein folding andstabilization; at the same time, it shed light on the higher communication ability of hydrophobicsubnetworks over the others. The results give an indication of the controlling role of hydrophobicsubclusters in determining protein's folding rate. The occurrences of higher perimeters of hydrophobic andcharged cliques imply the role of charged residues as well as hydrophobic residues in stabilizing the distantpart of primary structure of a protein through London van der Waals interaction.