Lactase activity of microorganisms

Sixty-two strains of yeasts, molds and bacteria were screened for lactase (β-D-galactosidase) activity. Strains exhibiting the enzyme activity were evaluated for cell yield as well as enzyme units available per litre of the medium, per g cell dry weight and per mg protein of their cell-free extracts. The molds exhibited lowest enzyme activity but highest cell yields, bacteria produced lowest cell yield and maximum enzyme activity. Cultures exhibiting very high activity among yeasts wereSaccharomyces fragilis (strain 3217) and among bacteriaStreptococcus cremoris (strain H),Lactobacillus bulgaricus (strain RTS and 1373) andLeuconostoc citrovorum (strain 8081).     

Artabotrys manoranjanii sp. nov. (Annonaceae) from the Andaman Islands,India

Artabotrys manoranjanii M. V. Ramana, J. Swamy & K. C. Mohan (Annonaceae), a new species from the foot hills of Saddle Peak National Park, north Andaman Islands, is described and illustrated. Its fleshy petals and prominent stigmas, distinguish it from all previously known species. Its affinity with A. parkinsonii Chatterjee, a Myanmar species, and A. grandiflorus King, a species from Malayan peninsula, is deliberated.     

Strain-induced inflammation in pulmonary alveolar tissue due to mechanical ventilation

Inflammation is the body’s attempt at self-protection to remove harmful stimuli, including damaged cells, irritants, or pathogens and begin the healing process. In this study, strain-induced inflammation in pulmonary alveolar tissue under high tidal volume is investigated through a combination of an inflammation model and fluid structure interaction (FSI) analysis. A realistic three-dimensional organ model for alveolar sacs is built, and FSI is employed to evaluate strain distribution in alveolar tissue for different tidal volume (TV) values under the mechanical ventilation (MV) condition. The alveolar tissue is treated as a hyperelastic solid and provides the environment for the tissue constituents. The influence of different strain distributions resulting from different tidal volumes is investigated. It is observed that strain is highly distributed in the inlet area. In addition, strain versus time curves in different locations through the alveolar model reveals that middle layers in the alveolar region would undergo higher levels of strain during breathing under the MV condition. Three different types of strain distributions in the alveolar region from the FSI simulation are transferred to the CA model to study population dynamics of cell constituents under MV for different TVs; 200, 500 and 1000 mL, respectively. The CA model results suggests that strain distribution plays a significant role in population dynamics. An interplay between strain magnitude and distribution appears to influence healing capability. Results suggest that increasing TV leads to an exponential rise in tissue damage by inflammation.     

Design, synthesis, and biological evaluation of 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines as cyclooxygenase-2 (COX-2) and lipoxygenase (LOX) inhibitors

A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, synthesized, and screened in vitro for anti-inflammatory activity. These compounds were designed for evaluation as dual inhibitors of cyclooxygenases (COX-1 and COX-2) and lipoxygenases (LOX-5, LOX-12, and LOX-15) that are responsible for inflammation and pain. All pyrazoline molecules prepared are optically active and compounds that are more potent in COX-2 inhibitory activity (5a and 5f) were resolved by chiral column and each enantiomer was tested for cyclooxygenase inhibitory activity. Molecular modeling and comparison of molecular models of 5a enantiomers with that of celecoxib model shows that 5a (enantiomer-1) and 5a (enantiomer-2) have more hydrogen bonding interactions in the catalytic domain of COX-2 enzyme than celecoxib. Compounds 5a, 5e, and 5f showed moderate to good LOX-5 and LOX-15 inhibitory activity and this is comparable to that of celecoxib and more potent than rofecoxib.     

Synthesis of fused pyran-carbahexopyranoses as glycosidase inhibitors

Synthesis of polyhydroxylated oxabicyclo[4,4,0]decanes, which constitute a new family of annulated carbasugars, has been accomplished in a stereoselective manner by employing readily available 1,2-anhydro-3,4,6-tri-O-benzyl-α-d-glycopyranoses.     

Transgenic <Emphasis Type="Italic">indica</Emphasis> rice cultivar ‘Swarna’ expressing a potato chymotrypsin inhibitor <Emphasis Type="Italic">pin2</Emphasis> gene show enhanced levels of resistance to yellow stem borer

Transgenic rice was developed from ‘Swarna’, the most popular indica rice cultivar (Oryza sativa L.) in South East Asia, with a potato chymotrypsin inhibitor gene (pin2) through Agrobacterium-mediated transformation. Four out of nine primary transgenic plants had a single-copy T-DNA insertion while other five plants had two copies. Mendelian pattern of inheritance of the transgene (pin2) was observed in the T₁ generation progeny plants. Whole plant bioassays conducted at both vegetative and reproductive stages and cut stem assays showed enhanced levels of resistance of transgenic rice against yellow stem borer. The transgenic rice lines with plant derived proteinase inhibitor genes would develop into resistant cultivars to fit into resistance breeding strategies as an important component of integrated pest management in rice.     

Optimization of hydrogen bonds for combined DNA/collagen complex

Many natural and biological systems including collagen and DNA polymers are formed by a process of molecular self-assembly. In this paper, we developed two novel structural models and built heterogeneous DNA/collagen complexes through a preferable arrangement of multiple hydrogen bonds (H-bonds) between DNA and collagen molecules. The simulation results based on three sets of criteria indicate that one of the models with five collagen molecules, which are positioned around each strand of DNA molecules emerged to form a suitable polymer complex with the maximum number of H-bonds. Our predictions quantitatively validated and agreed with the molecular structure reported by Mrevlishvili and Svintradze [2005. Int. J. Biol. Macromol. 36, 324-326].     

Complete Genome Sequence of the Aerobic CO-Oxidizing Thermophile Thermomicrobium roseum

In order to enrich the phylogenetic diversity represented in the available sequenced bacterial genomes and as part of an “Assembling the Tree of Life” project, we determined the genome sequence of Thermomicrobium roseum DSM 5159. T. roseum DSM 5159 is a red-pigmented, rod-shaped, Gram-negative extreme thermophile isolated from a hot spring that possesses both an atypical cell wall composition and an unusual cell membrane that is composed entirely of long-chain 1,2-diols. Its genome is composed of two circular DNA elements, one of 2,006,217 bp (referred to as the chromosome) and one of 919,596 bp (referred to as the megaplasmid). Strikingly, though few standard housekeeping genes are found on the megaplasmid, it does encode a complete system for chemotaxis including both chemosensory components and an entire flagellar apparatus. This is the first known example of a complete flagellar system being encoded on a plasmid and suggests a straightforward means for lateral transfer of flagellum-based motility. Phylogenomic analyses support the recent rRNA-based analyses that led to T. roseum being removed from the phylum Thermomicrobia and assigned to the phylum Chloroflexi. Because T. roseum is a deep-branching member of this phylum, analysis of its genome provides insights into the evolution of the Chloroflexi. In addition, even though this species is not photosynthetic, analysis of the genome provides some insight into the origins of photosynthesis in the Chloroflexi. Metabolic pathway reconstructions and experimental studies revealed new aspects of the biology of this species. For example, we present evidence that T. roseum oxidizes CO aerobically, making it the first thermophile known to do so. In addition, we propose that glycosylation of its carotenoids plays a crucial role in the adaptation of the cell membrane to this bacterium''s thermophilic lifestyle. Analyses of published metagenomic sequences from two hot springs similar to the one from which this strain was isolated, show that close relatives of T. roseum DSM 5159 are present but have some key differences from the strain sequenced.