The potential of Symbiont Ba cteria in Melo melo Gastropod found in Pekalongan Waters as a source of MDR antibacterial active compound

The increasing resistance of many pathogenic microorganisms against antibiotics compounds creates an alarming issue in medical world. This concern has created research opportunities in new antibiotics compounds as alternative options. The gastropod Melo melo is a species whose main diet consists of other smaller gastropods. However, Melo-melo does not have any self-defense mechanism save for its thin shell. To protect itself from various pathogenic bacteria existing in its food, Melo melo produces secondary metabolites, which are suspected to contain bioactive compounds with antibacterial properties. This fact puts Melo melo as a marine biota with potential as a source of new antibacterial compounds. This research aims to discover the potency of symbiont bacteria in the gastropod Melo melo with capabilities in producing Multi-drug resistant (MDR) antibacterial compounds. Samples of Melo melo are collected from the vicinity of Pekalongan waters, Central Java, Indonesia. This research begins with the isolation of symbiont bacteria, screening of symbiont bacteria with potency in MDR antibacterial activities, antibacterial test, and isolation of MDR clinical pathogenic bacteria. These protocols are then followed by antibacterial sensitivity test, and identification of bacterial species active against MDR by biochemical test and molecular analysis. Molecular analyses are carried out sequentially by DNA extraction, DNA amplification by PCR, and DNA sequencing. Results of 16S rDNA are analyzed using Genetix program and then followed by sequence analysis of the 16S rDNA. In this research, 11 bacteria in Melo melo are isolated and there are 4 isolates which show antibacterial activities against MDR bacteria from Pseudomonas sp. and Enterobacter sp species. Molecular analysis of the most active isolates identifies that isolate PM 26 matches in characteristics with Brevibacterium celere strain KMM 3637 with 89% homology match. On the other hand, biochemical test shows that isolate PM 26 is identical with Bacillus sp. This research concludes that symbiont bacteria found in Melo melo possess antibacterial activities against bacteria of MDR strain

A new Australian species of Luffa (Cucurbitaceae) and typification of two Australian Cucumis names, all based on specimens collected by Ferdinand Mueller in 1856

As a result of his botanical explorations in northern Australia, Ferdinand von Mueller named several Cucurbitaceae that molecular data now show to be distinct, requiring their resurrection from unjustified synonymy. We here describe and illustrate Luffa saccata F. Muell. ex I.Telford, validating a manuscript name listed under L. graveolens Roxb. since 1859, and we lectotypify Cucumis picrocarpus F. Muell. and C. jucundus F. Muell. The lectotype of the name C. jucundus, a synonym of C. melo, is mounted on the same sheet as the lectotype of C. picrocarpus, which is the sister species of the cultivated C. melo as shown in a recent publication

Phylogenetics of Cucumis (Cucurbitaceae)

Background: Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Results: Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Conclusion: Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification

Complete criterion for convex-Gaussian state detection

We present a new criterion that determines whether a fermionic state is a convex combination of pure Gaussian states. This criterion is complete and characterizes the set of convex-Gaussian states from the inside. If a state passes a program it is a convex-Gaussian state and any convex-Gaussian state can be approximated with arbitrary precision by states passing the criterion. The criterion is presented in the form of a sequence of solvable semidefinite programs. It is also complementary to the one developed by de Melo, Cwiklinski and Terhal, which aims at characterizing the set of convex-Gaussian states from the outside. Here we present an explicit proof that criterion by de Melo et al. is complete, by estimating a distance between an n-extendible state, a state that passes the criterion, to the set of convex-Gaussian states

On conformal measures and harmonic functions for group extensions

We prove a Perron-Frobenius-Ruelle theorem for group extensions of topological Markov chains based on a construction of $\sigma$-finite conformal measures and give applications to the construction of harmonic functions.Comment: To appear in Proceedings of "New Trends in Onedimensional Dynamics, celebrating the 70th birthday of Welington de Melo

On conformal measures and harmonic functions for group extensions

We prove a Perron-Frobenius-Ruelle theorem for group extensions of topological Markov chains based on a construction of $\sigma$-finite conformal measures and give applications to the construction of harmonic functions.Comment: To appear in Proceedings of "New Trends in Onedimensional Dynamics, celebrating the 70th birthday of Welington de Melo

Use of random amplified polymorphic DNA (RAPD) in differentiation of selected species of Cucumis grown in Southern India

Cucumis sativus (Cucumber), Cucumis melo var. acidulus (Vellari) and C. melo var. momordica (Snapmelon) are three species which are widely cultivated in India as vegetable crops. These species are distinguished based on leaf, hypanthium and fruit characteristics; however, large variation in morphological and fruit traits has been observed in different populations. A combination of morphological and random amplified polymorphic DNA (RAPD) analysis were carried out in these species to have a better understanding of the taxonomy. RAPD analysis of genomic DNA revealed that polymorphism with OPBE, OPBF primer series and banding pattern of OPBE-18, OPBF-03 and OPBF-15 were able to distinguish between C. sativus, C. melo var. acidulus and C. melo var. momordica.Key words: Cucumis sativus, Cucumis melo var. acidulus, Cucumis melo var. momordica, random amplified polymorphic DNA (RAPD)

Response of Cucumis melo accessions to isolates of Pseudoperonospora cubensis with different levels of virulence

Melon (Cucumis melo) is seriously affected by Pseudoperonospora cubensis, the causal agent of cucurbit downy mildew. Within C. melo, several genotypes resistant to P. cubensis have been described; however, we lack detailed experimental studies focused on deciphering variation in this host-pathogen interaction. The response of 115 accessions of C. melo to 8 isolates of P. cubensis was studied under controlled conditions. Pathogen isolates with low, medium and high virulence represented 8 distinct pathotypes. The virulence of isolates expressed by their published pathotypes conformed poorly to their virulence as observed on the C. melo accessions in this experiment. Collectively, 45 different reaction patterns were recorded. Most C. melo accessions (67) were highly susceptible to all isolates. Two accessions of C. melo subsp. agrestis (PI 614174 and PI 614442) were incompletely resistant to all isolates. The reaction of the remaining 46 accessions was race-specific. None of screened C. melo accessions expressed complete resistance to all isolates. Accession PI 315410 from India was resistant to 5 isolates and incompletely resistant to 2 others. The reduced development of at least one P. cubensis isolate was recorded on leaf discs of 17 accessions. Accessions with incomplete resistance to at least one isolate originated most frequently from India, Zimbabwe and Zambia. The study: a) confirmed the race-specificity of interactions between C. melo and P. cubensis, b) revealed C. melo subsp. agrestis as a taxon with potential field resistance to a number of races P. cubensis, and c) showed that within C. melo populations from India and southern Africa there are accessions completely or incompletely resistant to European races of P. cubensis