Structural prediction and comparative docking studies of psychrophilic ��- Galactosidase with lactose, ONPG and PNPG against its counter parts of mesophilic and thermophilic enzymes

Enzymes from psychrophiles catalyze the reactions at low temperatures with higher specific activity. Among all the psychrophilic enzymes produced, cold active β-galactosidase from marine psychrophiles revalorizes a new arena in numerous areas at industrial level. The hydrolysis of lactose in to glucose and galactose by cold active β-galactosidase offers a new promising approach in removal of lactose from milk to overcome the problem of lactose intolerance. Herein we propose, a 3D structure of cold active β-galactosidase enzyme sourced from Pseudoalteromonas haloplanktis by using Modeler 9v8 and best model was developed having 88% of favourable region in ramachandran plot. Modelling was followed by docking studies with the help of Auto dock 4.0 against the three substrates lactose, ONPG and PNPG. In addition, comparative docking studies were also performed for the 3D model of psychrophilic β-galactosidase with mesophilic and thermophilic enzymes. Docking studies revealed that binding affinity of enzyme towards the three different substrates is more for psychrophilic enzyme when compared with mesophilic and thermophilic enzymes. It indicates that the enzyme has high specific activity at low temperature when compared with mesophilic and thermophilic enzymes.     

Long non‐coding RNAs in melanoma

Melanoma is the most lethal cutaneous cancer with a highly aggressive and metastatic phenotype. While recent genetic and epigenetic studies have shed new insights into the mechanism of melanoma development, the involvement of regulatory non‐coding RNAs remain unclear. Long non‐coding RNAs (lncRNAs) are a group of endogenous non‐protein‐coding RNAs with the capacity to regulate gene expression at multiple levels. Recent evidences have shown that lncRNAs can regulate many cellular processes, such as cell proliferation, differentiation, migration and invasion. In the melanoma, deregulation of a number of lncRNAs, such as HOTAIR, MALAT1, BANCR, ANRIL, SPRY‐IT1 and SAMMSON, have been reported. Our review summarizes the functional role of lncRNAs in melanoma and their potential clinical application for diagnosis, prognostication and treatment.     

Blood oxidative stress generation after intraperitoneal administration of functionalized single-walled carbon nanotubes in rats

Single-walled carbon nanotubes (SWCNTs) have been proposed for various medical applications. However, their safety for human administration has not been yet fully demonstrated. In vitro studies have pointed oxidative stress as a mechanism involved in their cytotoxic effects. In the present study we have evaluated the capacity of DNA functionalized SWCNTs to induce oxidative stress in blood after intraperitoneal (ip) administration in rats. The presence of SWCNTs in blood was confirmed by Raman spectroscopy 30 minutes after their ip administration. Oxidative stress parameters (malondialdehyde - MDA, protein carbonyls - PC, antioxidant capacity measured as hydrogen donating capacity - HD, sulfhydryl groups - SH, glutathione - GSH and nitrites - NO) were assessed in blood at 3, 6, 24, respectively, and 48 hours after ip injection. MDA, PC and NO exhibited a significant increase at 3-6 hours interval from exposure, followed by a recovery trend. The levels of HD reached a bottom level at 6 hours after administration, while SH strongly decreased at 3 hours interval and increased slightly up to 48 hours without attending the initial values. GSH level recorded an increasing tendency at the 3rd hour, an incomplete recovery process at 24 hours followed by a secondary significant increase following a 48-hour interval. Significant inverse correlations were obtained between the PC and SH levels and between the NO and HD values. In conclusion, the ip administration of DNA functionalized SWCNT in rats results in oxidative stress generation in plasma, with a transient pattern of evolution.     

Influence of sequential oligopeptide carriers on the bioactive structure of conjugated epitopes: comparative study of the conformation of a Herpes simplex virus glycoprotein gD-1 epitope in the free and conjugated form, and protein "built-in" crystal structure

Synthetic carriers play an important role in immunogen presentation, due to their ability of inducing improved and specific responses to conjugated epitopes. Their influence on the bioactive conformation of the epitope, though admittedly crucial for relevant in vitro and in vivo applications, is difficult to evaluate, given the usual lack of information on the complex conformational features determined by the nature of the carrier and the mode of ligation. Using the Herpes simplex virus glycoprotein D-1 epitope (Leu(9)-Lys-Nle-Ala-Asp-Pro-Asn-Arg-Phe-Arg-Gly-Lys-Asp-Leu(22)) as a model, we have performed a detailed conformational analysis on the free epitope peptide in solution and on three constructs in which the epitope was conjugated to sequential oligopeptide carriers {Ac-[Lys-Aib-Gly](4)-OH (SOC(4))} (through either a thioether or an amide bond; Ac: acetyl) and polytuftsin oligomers {H-[Thr-Lys-Pro-Lys-Gly](4)-NH(2) (T20)}, (through a thioether bond). The analysis of the epitope conformation in the parent protein, in carrier-conjugated and free form, suggests that the beta-turn structure of the -Asp(13)-Pro-Asn-Arg(16)- segment is highly conserved and independent of the epitope form. However, small conformational variations were observed at the C-terminal part of the epitope, depending on the nature of the carrier.     

Changes in odor quality discrimination following recovery from olfactory nerve transection

Following recovery from olfactory nerve transection, animals regain their ability to discriminate between odors. Odor discrimination is restored after new neurons establish connections with the olfactory bulb. However, it is not known if the new connections alter odor quality perception. To address this question, 20 adult hamsters were first trained to discriminate between cinnamon and strawberry odors. After reaching criterion (> or = 90% correct response), half of the animals received a bilateral nerve transection (BTX) and half a surgical sham procedure. Animals were not tested again until day 40, a point in recovery when connections are re-established with the bulb. When BTX animals were tested without food reinforcement, they could not perform the odor discrimination task. Sham animals, however, could discriminate, demonstrating that the behavioral response had not been extinguished during the 40 day period. When reinforcement was resumed, BTX animals were able to discriminate between cinnamon and strawberry after four test sessions. In addition, their ability to discriminate between these two familiar odors was no different than that of BTX and sham animals tested with two novel odors, baby powder and coffee. These findings suggest that, after recovery from nerve transection, there are alterations in sensory perception and that restoration of odor quality discrimination requires that the animal must again learn to associate individual odor sensations with a behavioral response.      

Photoacoustic and photothermal cytometry using photoswitchable proteins and nanoparticles with ultrasharp resonances

In the article by E. I. Galanzha et al. (doi: http://dx.doi.org/10.1002/jbio.201300140 ), published in J. Biophotonics 8, 81–93 (2015), the Conflict of Interest statement is missing. This erratum is published to correct this.     

Genotoxicity of TiO(2) anatase nanoparticles in B6C3F1 male mice evaluated using Pig-a and flow cytometric micronucleus assays

In vivo micronucleus and Pig-a (phosphatidylinositol glycan, class A gene) mutation assays were conducted to evaluate the genotoxicity of 10 nm titanium dioxide anatase nanoparticles (TiO(2)-NPs) in mice. Groups of five 6-7-week-old male B6C3F1 mice were treated intravenously for three consecutive days with 0.5, 5.0, and 50 mg/kg TiO(2)-NPs for the two assays; mouse blood was sampled one day before the treatment and on Day 4, and Weeks 1, 2, 4, and 6 after the beginning of the treatment; Pig-a mutant frequencies were determined at Day -1 and Weeks 1, 2, 4 and 6, while percent micronucleated-reticulocyte (%MN-RET) frequencies were measured on Day 4 only. Additional animals were treated intravenously with three daily doses of 50 mg.kg TiO(2)-NPs for the measurement of titanium levels in bone marrow after 4, 24, and 48 h of the last treatment. The measurement indicated that the accumulation of the nanoparticles reached the peak in the tissue 4 h after the administration and the levels were maintained for a few days. No increase in either Pig-a mutant frequency of the frequency of %MN-RETs was detected, although the %RETs was reduced in the treated animals on Day 4 in a dose-dependent manner indicating cytotoxicity of TiO(2)-NPs in the bone marrow. These results suggest that although TiO(2)-NPs can reach the mouse bone marrow and are capable of inducing cytotoxicity, the nanoparticles are not genotoxic when assessed with in vivo micronucleus and Pig-a gene mutation tests.