Search results for "Systematics"

Investigation of the steps involved in the difference of susceptibility of Ephestia kuehniella and Spodoptera littoralis to the Bacillus thuringiensi…

2011

BUPM95 is a Bacillus thuringiensis subsp. kurstaki strain producing the Vip3Aa16 toxin with an interesting insecticidal activity against the Lepidopteran larvae Ephestia kuehniella. Study of different steps in the mode of action of this Vegetative Insecticidal Protein on the Mediterranean flour moth (E. kuehniella) was carried out in the aim to investigate the origin of the higher susceptibility of this insect to Vip3Aa16 toxin compared to that of the Egyptian cotton leaf worm Spodoptera littoralis. Using E. kuehniella gut juice, protoxin proteolysis generated a major band corresponding to the active toxin and another band of about 22kDa, whereas the activation of Vip3Aa16 by S. littoralis …

Evolutionary and structural analyses of GDAP1, involved in Charcot-Marie-Tooth disease, characterize a novel class of glutathione transferase-related…

2003

Mutations in the Ganglioside-induced differentiation-associated protein-1 (GDAP1) gene cause autosomal recessive Charcot-Marie-Tooth disease type 4A. The protein encoded by GDAP1 shows clear similarity to glutathione transferases (also known as glutathione S-transferases or GSTs). The human genome contains a paralog of GDAP1 called GDAP1L1. Using comparative genomics, we show that orthologs of GDAP1 and GDAP1L1 are found in mammals, birds, amphibians, and fishes. Likely orthologs of those genes in invertebrates and a low but consistent similarity with some plant and eubacterial genes have also been found. We demonstrate that GDAP1 and GDAP1L1 do not belong to any of the known classes of GST…

A Stevedore's protein knot.

2009

Protein knots, mostly regarded as intriguing oddities, are gradually being recognized as significant structural motifs. Seven distinctly knotted folds have already been identified. It is by and large unclear how these exceptional structures actually fold, and only recently, experiments and simulations have begun to shed some light on this issue. In checking the new protein structures submitted to the Protein Data Bank, we encountered the most complex and the smallest knots to date: A recently uncovered α-haloacid dehalogenase structure contains a knot with six crossings, a so-called Stevedore knot, in a projection onto a plane. The smallest protein knot is present in an as yet unclassified …

Bioinformatic flowchart and database to investigate the origins and diversity of Clan AA peptidases

2009

Abstract Background Clan AA of aspartic peptidases relates the family of pepsin monomers evolutionarily with all dimeric peptidases encoded by eukaryotic LTR retroelements. Recent findings describing various pools of single-domain nonviral host peptidases, in prokaryotes and eukaryotes, indicate that the diversity of clan AA is larger than previously thought. The ensuing approach to investigate this enzyme group is by studying its phylogeny. However, clan AA is a difficult case to study due to the low similarity and different rates of evolution. This work is an ongoing attempt to investigate the different clan AA families to understand the cause of their diversity. Results In this paper, we…

Proteomics as a tool to monitor plant-microbe endosymbioses in the rhizosphere

2004

In recent years, outstanding molecular approaches have been used to investigate genes and functions involved in plant-microbe endosymbioses. In this review, we outline the use of proteomic analysis, based on two-dimensional electrophoresis and mass spectrometry, to characterize symbiosis-related proteins. During the last decade, proteomics succeeded in identifying about 400 proteins associated with the development and functioning of both mycorrhizal and rhizobial symbioses. Further progress in prefractionation procedures is expected to allow the detection of symbiotic proteins showing low abundance or being present in certain cell compartments.

Do distantly related parasites rely on the same proximate factors to alter the behaviour of their hosts?

2006

Phylogenetically unrelated parasites often increase the chances of their transmission by inducing similar phenotypic changes in their hosts. However, it is not known whether these convergent strategies rely on the same biochemical precursors. In this paper, we explored such aspects by studying two gammarid species ( Gammarus insensibilis and Gammarus pulex ; Crustacea: Amphipoda: Gammaridae) serving as intermediate hosts in the life cycle of two distantly related parasites: the trematode, Microphallus papillorobustus and the acanthocephalan, Polymorphus minutus . Both these parasite species are known to manipulate the behaviour of their amphipod hosts, bringing them towards the water surfa…

The Wnt-specific astacin proteinase HAS-7 restricts head organizer formation in Hydra

2021

Abstract Background The Hydra head organizer acts as a signaling center that initiates and maintains the primary body axis in steady state polyps and during budding or regeneration. Wnt/beta-Catenin signaling functions as a primary cue controlling this process, but how Wnt ligand activity is locally restricted at the protein level is poorly understood. Here we report a proteomic analysis of Hydra head tissue leading to the identification of an astacin family proteinase as a Wnt processing factor. Results Hydra astacin-7 (HAS-7) is expressed from gland cells as an apical-distal gradient in the body column, peaking close beneath the tentacle zone. HAS-7 siRNA knockdown abrogates HyWnt3 proteo…

Phenols content and 2-D electrophoresis protein pattern: a promising tool to monitor Posidonia meadows health state

2007

Abstract Background The endemic seagrass Posidonia oceanica (L.) Delile colonizes soft bottoms producing highly productive meadows that play a crucial role in coastal ecosystems dynamics. Human activities and natural events are responsible for a widespread meadows regression; to date the identification of "diagnostic" tools to monitor conservation status is a critical issue. In this study the feasibility of a novel tool to evaluate ecological impacts on Posidonia meadows has been tested. Quantification of a putative stress indicator, i.e. phenols content, has been coupled to 2-D electrophoretic protein analysis of rhizome samples. Results The overall expression pattern from Posidonia rhizom…

Book review: The Ethics of Protocells: Moral and Social Implications of Creating Life in the Laboratory

2010

Provenance of sediments during subduction of Palaeotethys: Detrital zircon ages and olistolith analysis in Palaeozoic sediments from Chios Island, Gr…

2008

Abstract Detrital zircon geochronology and analysis of fossiliferous olistoliths from Chios Island, Greece, are used here to constrain terrane accretion processes and the provenance of crustal sources for sediments during the subduction of (a branch of) the Palaeotethys Ocean. U/Pb ages obtained by ion microprobe (SHRIMP-II) analyses of detrital zircons from a Carboniferous greywacke belonging to the tectonostratigraphic Lower Unit of Chios gave major age groups of 2150–1890 Ma, 640–540 Ma, 505–475 Ma and 365–322 Ma. Detrital zircons from a Permian–Triassic sandstone yielded prominent age clusters of 2200–1840 Ma, 1100–910 Ma, 625–560 Ma and 385–370 Ma. The lack of zircon ages between 1.8 a…