Cellulolytic, fermentative, and methanogenic guilds in benthic periphyton mats from the Florida Everglades

Phosphorus enrichment caused by runoff from agricultural areas has resulted in ecosystem-level changes in the northern Florida Everglades, including a loss of periphyton mats from nutrient-impacted areas. The potential for methanogenesis resulting from the anaerobic decomposition of cellulose and fermentation products, and the microorganisms responsible for these processes, were studied in mats from a region not impacted by nutrient enrichment. Methane was produced from periphyton incubated with cellulose, propionate, butyrate, and formate, with an accumulation of fatty acids in incubations. The accumulation of fatty acids may have been caused by the inhibition of syntrophic oxidation, a potentially significant route for methane production in soils. Sequence analysis of 16S rRNA genes characteristic of Clostridium, the primary genus responsible for anaerobic decomposition and fermentation in soils of the area, indicated that Clostridium Cluster I assemblages present in the mat differed from those in the soils of the area. Significantly, sequences characteristic of the Clostridium group that dominates the soils of the area, group XIV, were not detected in the mat. These results indicate that benthic periphyton is probably a significant source of methane in the Everglades, and the responsible microorganisms differ significantly from those in the soils of the area.     

Immunotoxicity of carbaryl in chicken

Effect of methyl carbonate pesticide, carbonyl, was studied on macrophage functions, lymphocyte proliferation and delayed type hypersensitivity response. Sixteen adult chicken, vaccinated against Newcaslte disease, were procured and randomly divided in two experimental groups. Chicken of group I served as control, while group II birds were given carbaryl at 20 ppm (No observable effect level, NOEL) in feed for 3 months. To measure the functional activity of phagocytic cells, nitroblue tetrazolium (NBT) reduction test was performed on peripheral blood leucocytes. Concanvalin A (Con-A) and lipopolysaccharide stimulated proliferation of T and B lymphocytes was assessed using MTT dye method. At the end of experiment, the phagocytic capacities of macrophages were significantly reduced in carbaryl treated group. Lymphocyte proliferation responses to Con-A and LPS were (23 and 28%, respectively lower) in chicken fed with carbaryl. Delayed hypersensitivity reaction to tuberculin was reduced to 77% of control values indicating inhibition of cell mediated immune response. The present study suggested of immunosuppressive effect of (NOEL dose carbaryl) in chicken.     

Phosphate solubilization potential and stress tolerance of Eupenicillium parvum from tea soil

Eupenicillium parvum was recorded for first time during isolation of phosphate-solubilizing microorganisms from the tea rhizosphere. The fungus developed a phosphate solubilization zone on modified Pikovskaya agar, supplemented with tricalcium phosphate. Quantitative estimation of phosphate solubilization in Pikovskaya broth showed high solubilization of tricalcium phosphate and aluminium phosphate. The fungus also solubilized North Carolina rock phosphate and Mussoorie rock phosphate, and exhibited high levels of tolerance against desiccation, acidity, salinity, aluminium, and iron. Solubilization of inorganic phosphates by the fungus was also observed under high stress levels of aluminium, iron, and desiccation, though the significant decline in phosphate solubilization was marked in the presence of aluminium than iron. The fungal isolate showed 100 % identity with E. parvum strain NRRL 2095 ITS 1, 5.8S rRNA gene and ITS 2, complete sequence; and 28S rRNA gene, partial sequence.     

Isolation and characterization of embryonic stem cell-like cells from in vitro-produced buffalo (Bubalus bubalis) embryos

This study was carried out to isolate and characterize buffalo embryonic stem (ES) cell-like cells from in vitro-produced embryos. Inner cell mass (ICM) cells were isolated either mechanically or by enzymatic digestion from 120 blastocysts whereas 28 morulae were used for the isolation of blastomeres mechanically. The ICM cells/ blastomeres were cultured on mitomycin-C-treated feeder layer. Primary cell colony formation was higher (P < 0.05) for hatched blastocysts (73.1%, 30/41) than that for early/expanded blastocysts (25.3%, 20/79). However, no primary cell colonies were formed when blastomeres obtained from morulae were cultured. Primary colonies were formed in 14.1% (12/85) of intact blastocyst culture, which was significantly lower (P < 0.05) than that of 41.6% for ICM culture. These colonies were separated by enzymatic or mechanical disaggregation. Using mechanical disaggregation method, the cells remained undifferentiated and two buffalo ES cell-like cell lines (bES1, bES2) continued to grow in culture up to eight passages. However, disassociation through enzymatic method resulted in differentiation. Undifferentiated cells exhibited stem cell morphological features, normal chromosomal morphology, and expressed specific markers such as alkaline phosphatase (AP) and Oct-4. Cells formed embryoid bodies (EBs) in suspension culture; extended culture of EBs resulted in formation of cystic EBs. Following prolonged in vitro culture, these cells differentiated into several types of cells including neuron-like and epithelium-like cells. Furthermore, the vitrified-thawed ES cell-like cells also exhibited typical stem cell characteristics. In conclusion, buffalo ES cell-like cells could be isolated from in vitro-produced blastocysts and maintained in vitro for prolonged periods of time.     

Observation of glycine zipper and unanticipated occurrence of ambidextrous helices in the crystal structure of a chiral undecapeptide

Background  

The de novo design of peptides and proteins has recently surfaced as an approach for investigating protein structure and function. This approach vitally tests our knowledge of protein folding and function, while also laying the groundwork for the fabrication of proteins with properties not precedented in nature. The success of these studies relies heavily on the ability to design relatively short peptides that can espouse stable secondary structures. To this end, substitution with α, β-dehydroamino acids, especially α, β-dehydrophenylalanine (ΔPhe) comes in use for spawning well-defined structural motifs. Introduction of ΔPhe induces β-bends in small and 3₁₀-helices in longer peptide sequences.     

Metalloids in plants: A systematic discussion beyond description

Metalloids represent a wide range of elements with intermediate physiochemical properties between metals and non-metals. Many of the metalloids, like boron, selenium, and silicon are known to be essential or quasi-essential for plant growth. In contrast, metalloids viz. arsenic and germanium are toxic to plant growth. The toxicity of metalloids largely depends on their concentration within the living cells. Some elements, at low concentration, may be beneficial for plant growth and development; however, when present at high concentration, they often exert negative effects. In this regard, understanding the molecular mechanisms involved in the uptake of metalloids by roots, their subsequent transport to different tissues and inter/intra-cellular redistribution has great importance. The mechanisms of metalloids' uptake have been well studied in plants. Also, various transporters, as well as membrane channels involved in these processes, have been identified. In this review, we have discussed in detail the aspects concerning the positive/negative effects of different metalloids on plants. We have also provided a thorough account of the uptake, transport, and accumulation, along with the molecular mechanisms underlying the response of plants to these metalloids. Additionally, we have brought up the previous theories and debates about the role and effects of metalloids in plants with insightful discussions based on the current knowledge.     

Assessment of culture medium without commercial ammonium nitrate for in vitro culture of industrially important plant species

Plant Cell, Tissue and Organ Culture (PCTOC) - Ammonium nitrate (AN) is one of the major nitrogen sources of Murashige and Skoog (MS) medium. It is prohibited in various countries, including India...