4 research outputs found
Range Information Systems Management (RISM) Phase 1 Report
RISM investigated alternative approaches, technologies, and communication network architectures to facilitate building the Spaceports and Ranges of the future. RISM started by document most existing US ranges and their capabilities. In parallel, RISM obtained inputs from the following: 1) NASA and NASA-contractor engineers and managers, and; 2) Aerospace leaders from Government, Academia, and Industry, participating through the Space Based Range Distributed System Working Group (SBRDSWG), many of whom are also; 3) Members of the Advanced Range Technology Working Group (ARTWG) subgroups, and; 4) Members of the Advanced Spaceport Technology Working Group (ASTWG). These diverse inputs helped to envision advanced technologies for implementing future Ranges and Range systems that builds on today s cabled and wireless legacy infrastructures while seamlessly integrating both today s emerging and tomorrow s building-block communication techniques. The fundamental key is to envision a transition to a Space Based Range Distributed Subsystem. The enabling concept is to identify the specific needs of Range users that can be solved through applying emerging communication tec
Synthetic bacterial communities for plant growth promotion
PhD ThesisIncreasing food demands have driven the adoption of new global strategies to intensify
productivity without relying on heavy chemical treatments. In the last decades, plant-growth
promoting rhizobacteria (PGPR) have emerged as potential biofertilisers and biopesticides in
agriculture. The overall aim of this study was to research and develop approaches to
genetically engineer PGPR to improve their beneficial activities toward the plant partner.
A simplified PGPR community, a Bacillus consortium of three strains, was adopted to
study the complexity of the interactions occurring within the consortium and the plant
microbiome. Firstly, the comparative genomic analysis of the consortium highlighted the
unique and shared features responsible for plant promotion, microbial interaction and
cooperation among the strains (niche partitioning, organisation in biofilms with cooperative
mechanisms of quorum sensing, cell density control and antibiotic detoxification). Flux
balance analysis identified cross-feeding interactions among the strains and the metabolic
capability of the consortium to provide nitrogen to the plant, transforming it into forms
available for plant utilisation.
The consortium PGP potential was then investigated in vitro (LEAP mesocosm assay) and
in vivo (pot experiment) on the vegetable crop Brassica rapa. These tests show increased plant
growth when the strains were inoculated together rather than individually and when the
consortium was used as a supplement of the natural bulk soil microbiome. The in silico study
and the plant experiments highlighted areas for genetic improvement of the consortium
genomes.
Lastly, this work describes the development of a conjugation system that could be used
to efficiently engineer non-domesticated bacteria and bacterial communities, such as
rhizobacteria and plant microbiomes. The system, based on the plasmid pLS20, was developed
in Bacillus subtilis 168 and successfully tested on twenty-three wild type Bacillus strains and
three rhizobacillus communities.
The research presented here provides tools and approaches for the genetic
manipulation of rhizobacterial communities, with the ultimate aim of generating sustainable
agricultural bioformulations and sheds light on the complex interactions that can occur in a
model microbial PGPR consortia
Ultrasensitive detection of toxocara canis excretory-secretory antigens by a nanobody electrochemical magnetosensor assay.
peer reviewedHuman Toxocariasis (HT) is a zoonotic disease caused by the migration
of the larval stage of the roundworm Toxocara canis in the human host.
Despite of being the most cosmopolitan helminthiasis worldwide, its
diagnosis is elusive. Currently, the detection of specific immunoglobulins
IgG against the Toxocara Excretory-Secretory Antigens (TES), combined
with clinical and epidemiological criteria is the only strategy to diagnose
HT. Cross-reactivity with other parasites and the inability to distinguish
between past and active infections are the main limitations of this
approach. Here, we present a sensitive and specific novel strategy to
detect and quantify TES, aiming to identify active cases of HT. High
specificity is achieved by making use of nanobodies (Nbs), recombinant
single variable domain antibodies obtained from camelids, that due to
their small molecular size (15kDa) can recognize hidden epitopes not
accessible to conventional antibodies. High sensitivity is attained by the
design of an electrochemical magnetosensor with an amperometric readout
with all components of the assay mixed in one single step. Through
this strategy, 10-fold higher sensitivity than a conventional sandwich
ELISA was achieved. The assay reached a limit of detection of 2 and15
pg/ml in PBST20 0.05% or serum, spiked with TES, respectively. These
limits of detection are sufficient to detect clinically relevant toxocaral
infections. Furthermore, our nanobodies showed no cross-reactivity
with antigens from Ascaris lumbricoides or Ascaris suum. This is to our
knowledge, the most sensitive method to detect and quantify TES so far,
and has great potential to significantly improve diagnosis of HT. Moreover,
the characteristics of our electrochemical assay are promising for the
development of point of care diagnostic systems using nanobodies as a
versatile and innovative alternative to antibodies. The next step will be the
validation of the assay in clinical and epidemiological contexts