COMPARATIVE IN-VITRO ANTIBACTERIAL AND ANTIFUNGAL ATTRIBUTES OF DIFFERENT SOLVENT EXTRACTS FROM LEAF, BARK, ROOT AND INFLORESCENCE OF MEMECYLON UMBELLATUM BURM.

This paper describes the antibacterial and antifungal activities and Minimum Inhibitory Concentration (MIC) of different solvent (pet. ether, chloroform, ethyl acetate, acetone, methanol and water) extracts of leaves, bark, root and inflorescence of Memecylon umbellatum burm. The percent yields from leaves, bark, root and inflorescence was found to be 0.2062 to 2.836, 0.0601 to 0.5142, 0.050 to 1.425, 0.0210 to 0.717 respectively. Overall, acetone extract produced from the leaves exhibited significantly (P < 0.05) higher antibacterial activity along with superior antifungal activity. MIC for acetone and ethyl acetate extract of leaf was found to be 0.5 mg for the entire organisms compared to 3-15 mg for other extracts. Such study will explore pharmacological activity of the tested parts of Memecylon umbellatum burm especially, the leaves which might be valuable for therapeutic applications

FAMC: Face Authentication for Mobile Concurrence

It has been observed in the last decades that face recognition has acquired a large amount of attention and curiosity. Benefits of this have been seen in quite a few applications. An architecture which has been implemented earlier addresses the face analysis domain. As compared to other biometrics, face recognition is more advantageous but it is particularly subject to spoofing. The whole cost of the system increases since the accuracy of this technique involves the estimation of the three dimensionality of faces. An effective and efficient solution for face spoofing has been proposed in the paper. The growing use of mobile devices has been a growing concern due to their ability to store and exchange sensitive data. Thus this has given encouragement to the interest of people, to exploit their abilities, from one side, and to protect users from malicious data, on the other side. It is important to develop and deliver secure access in this scenario and identification protocols on mobile platforms are another upcoming aspect that also requires attention to deal on the commercial and social use of identity management system. After all these conclusions, the earlier architecture proposes biometrics as the choice for technology which has been also implemented and described in the earlier architecture. The earlier architecture is designed for mobile devices. This architecture thus acts as an embedded application that provides both verification and identification functionality. It includes identity management to support social activities. Examples of identity management system are finding doubles in a social network. Privacy has been provided by these functionalities which help to overcome the security concern. The architecture of FAMC: Face Authentication for Mobile Concurrence is modular. Functionalities like image acquisition, anti-spoofing, face detection, face segmentation; feature extraction and face matching have been provided by its implementation. The behavior of FAMC allows for recognition and best biometrics sample selection. DOI: 10.17762/ijritcc2321-8169.150310

Fitness of Isogenic Colony Morphology Variants of Pseudomonas aeruginosa in Murine Airway Infection

Chronic lung infections with Pseudomonas aeruginosa are associated with the diversification of the persisting clone into niche specialists and morphotypes, a phenomenon called ‘dissociative behaviour’. To explore the potential of P. aeruginosa to change its morphotype by single step loss-of–function mutagenesis, a signature-tagged mini-Tn5 plasposon library of the cystic fibrosis airway isolate TBCF10839 was screened for colony morphology variants under nine different conditions in vitro. Transposon insertion into 1% of the genome changed colony morphology into eight discernable morphotypes. Half of the 55 targets encode features of primary or secondary metabolism whereby quinolone production was frequently affected. In the other half the transposon had inserted into genes of the functional categories transport, regulation or motility/chemotaxis. To mimic dissociative behaviour of isogenic strains in lungs, pools of 25 colony morphology variants were tested for competitive fitness in an acute murine airway infection model. Six of the 55 mutants either grew better or worse in vivo than in vitro, respectively. Metabolic proficiency of the colony morphology variant was a key determinant for survival in murine airways. The most common morphotype of self-destructive autolysis did unexpectedly not impair fitness. Transposon insertions into homologous genes of strain PAO1 did not reproduce the TBCF10839 mutant morphotypes for 16 of 19 examined loci pointing to an important role of the genetic background on colony morphology. Depending on the chosen P. aeruginosa strain, functional genome scans will explore other areas of the evolutionary landscape. Based on our discordant findings of mutant phenotypes in P. aeruginosa strains PAO1, PA14 and TBCF10839, we conclude that the current focus on few reference strains may miss modes of niche adaptation and dissociative behaviour that are relevant for the microevolution of complex traits in the wild

Nutrient Availability as a Mechanism for Selection of Antibiotic Tolerant Pseudomonas aeruginosa within the CF Airway

Microbes are subjected to selective pressures during chronic infections of host tissues. Pseudomonas aeruginosa isolates with inactivating mutations in the transcriptional regulator LasR are frequently selected within the airways of people with cystic fibrosis (CF), and infection with these isolates has been associated with poorer lung function outcomes. The mechanisms underlying selection for lasR mutation are unknown but have been postulated to involve the abundance of specific nutrients within CF airway secretions. We characterized lasR mutant P. aeruginosa strains and isolates to identify conditions found in CF airways that select for growth of lasR mutants. Relative to wild-type P. aeruginosa, lasR mutants exhibited a dramatic metabolic shift, including decreased oxygen consumption and increased nitrate utilization, that is predicted to confer increased fitness within the nutrient conditions known to occur in CF airways. This metabolic shift exhibited by lasR mutants conferred resistance to two antibiotics used frequently in CF care, tobramycin and ciprofloxacin, even under oxygen-dependent growth conditions, yet selection for these mutants in vitro did not require preceding antibiotic exposure. The selection for loss of LasR function in vivo, and the associated adverse clinical impact, could be due to increased bacterial growth in the oxygen-poor and nitrate-rich CF airway, and from the resulting resistance to therapeutic antibiotics. The metabolic similarities among diverse chronic infection-adapted bacteria suggest a common mode of adaptation and antibiotic resistance during chronic infection that is primarily driven by bacterial metabolic shifts in response to nutrient availability within host tissues

Epistatic Roles for Pseudomonas aeruginosa MutS and DinB (DNA Pol IV) in Coping with Reactive Oxygen Species-Induced DNA Damage

Pseudomonas aeruginosa is especially adept at colonizing the airways of individuals afflicted with the autosomal recessive disease cystic fibrosis (CF). CF patients suffer from chronic airway inflammation, which contributes to lung deterioration. Once established in the airways, P. aeruginosa continuously adapts to the changing environment, in part through acquisition of beneficial mutations via a process termed pathoadaptation. MutS and DinB are proposed to play opposing roles in P. aeruginosa pathoadaptation: MutS acts in replication-coupled mismatch repair, which acts to limit spontaneous mutations; in contrast, DinB (DNA polymerase IV) catalyzes error-prone bypass of DNA lesions, contributing to mutations. As part of an ongoing effort to understand mechanisms underlying P. aeruginosa pathoadaptation, we characterized hydrogen peroxide (H2O2)-induced phenotypes of isogenic P. aeruginosa strains bearing different combinations of mutS and dinB alleles. Our results demonstrate an unexpected epistatic relationship between mutS and dinB with respect to H2O2-induced cell killing involving error-prone repair and/or tolerance of oxidized DNA lesions. In striking contrast to these error-prone roles, both MutS and DinB played largely accurate roles in coping with DNA lesions induced by ultraviolet light, mitomycin C, or 4-nitroquinilone 1-oxide. Models discussing roles for MutS and DinB functionality in DNA damage-induced mutagenesis, particularly during CF airway colonization and subsequent P. aeruginosa pathoadaptation are discussed

A eukaryotic-type signalling system of Pseudomonas aeruginosa contributes to oxidative stress resistance, intracellular survival and virulence

<p>Abstract</p> <p>Background</p> <p>The genome of <it>Pseudomonas aeruginosa </it>contains at least three genes encoding eukaryotic-type Ser/Thr protein kinases, one of which, <it>ppkA</it>, has been implicated in <it>P. aeruginosa </it>virulence. Together with the adjacent <it>pppA </it>phosphatase gene, they belong to the type VI secretion system (H1-T6SS) locus, which is important for bacterial pathogenesis. To determine the biological function of this protein pair, we prepared a <it>pppA-ppkA </it>double mutant and characterised its phenotype and transcriptomic profiles.</p> <p>Results</p> <p>Phenotypic studies revealed that the mutant grew slower than the wild-type strain in minimal media and exhibited reduced secretion of pyoverdine. In addition, the mutant had altered sensitivity to oxidative and hyperosmotic stress conditions. Consequently, mutant cells had an impaired ability to survive in murine macrophages and an attenuated virulence in the plant model of infection. Whole-genome transcriptome analysis revealed that <it>pppA-ppkA </it>deletion affects the expression of oxidative stress-responsive genes, stationary phase σ-factor RpoS-regulated genes, and quorum-sensing regulons. The transcriptome of the <it>pppA-ppkA </it>mutant was also analysed under conditions of oxidative stress and showed an impaired response to the stress, manifested by a weaker induction of stress adaptation genes as well as the genes of the SOS regulon. In addition, expression of either RpoS-regulated genes or quorum-sensing-dependent genes was also affected. Complementation analysis confirmed that the transcription levels of the differentially expressed genes were specifically restored when the <it>pppA </it>and <it>ppkA </it>genes were expressed ectopically.</p> <p>Conclusions</p> <p>Our results suggest that in addition to its crucial role in controlling the activity of <it>P. aeruginosa </it>H1-T6SS at the post-translational level, the PppA-PpkA pair also affects the transcription of stress-responsive genes. Based on these data, it is likely that the reduced virulence of the mutant strain results from an impaired ability to survive in the host due to the limited response to stress conditions.</p

Pigeonpea nutrition and its improvement

Pigeonpea (Cajanus cajan [L.] Millsp.), known by several vernacular and names such as red gram, tuar, Angola pea. yellow dhal and oil dhal, is one of the major grain legume crops of the tropics and sub-tropics. It is a crop of small holder dryland fmmers because it can grow well under subsistence level of agriculture and provides nutritive food, fodder, and fuel wood. It also improves soil by fixing atmospheric nitrogen. India by far is the largest pigeonpea producer it is consumed as decorticated split peas, popularly called as 'dhaL' In other countries, its consumption as whole dty and green vegetable is popular. Its foliage is used as fodder and milling by-products [onn an excellent feed for domestic animals. Pigeonpea seeds contain about 20-22% protein and appreciable amounts of essential amino.acids and minerals. DehuHing and boiling treatments of seeds get rid of the most antinutritional factors as tannins and enzyme inhibitors. Seed storage causes considerable losses in the quality of this legume. The seed protein of pigeonpea has been successfully enhanced by breeding from 20-22% to 28-30%. Such lines also agronomically performed well and have acceptable and color. The high-protein lines were found nutritionally superior to the cultivars because they would provide more quantities of utilizable protein and sulfur-containing amino acids