Rhamnolipid biosurfactants: evolutionary implications,applications and future prospects from untapped marine resource

Rhamnolipid-biosurfactants are known to be produced by the genus Pseudomonas, however recent literature reported that rhamnolipids (RLs) are distributed among diverse microbial genera. To integrate the evolutionary implications of rhamnosyl transferase among various groups of microorganisms, a comprehensive comparative motif analysis was performed amongst bacterial producers. Findings on new RL-producing microorganism is helpful from a biotechnological perspective and to replace infective P. aeruginosa strains which ultimately ensure industrially safe production of RLs. Halotolerant biosurfactants are required for efficient bioremediation of marine oil spills. An insight on the exploitation of marine microbes as the potential source of RL biosurfactants is highlighted in the present review. An economic production process, solid-state fermentation using agro-industrial and industrial waste would increase the scope of biosurfactants commercialization. Potential and prospective applications of RL-biosurfactants including hydrocarbon bioremediation, heavy metal removal, antibiofilm activity/biofilm disruption and greener synthesis of nanoparticles are highlighted in this review.     

The untapped potential of the GENSAT mice—A valuable resource for developmental biology

Gene Expression Nervous System Atlas (GENSAT) transgenic mice express EGFP, tdTomato, or Cre recombinase in a wide range of cell types. The mice and the bacterial artificial chromosome transgenes are available from repositories (MMRRC or CHORI), thereby making these resources readily available to the research community. This resource of 1,386 transgenic lines was developed and validated for neuroscience research. However, GENSAT mice have many potential applications in other contexts including studies of development outside of the CNS. The cell type‐specific expression of fluorescent proteins in these mice has been used to identify cells in living embryos, in living embryo explants, and in stem or progenitor cell populations in postnatal tissues. The large number of fluorescent protein driver lines generated by GENSAT greatly expands the range of cell type markers that can be used for live cell sorting. In addition, the GENSAT project has generated 278 new Cre driver lines. This review provides an overview of the GENSAT lines and information for identifying lines that may be useful for a particular application. I also provide a review of the few published cases in which GENSAT mice have been used for studies of embryonic development or analysis of stem/progenitor cells in nonneural tissues. genesis 54:245–256, 2016. © 2016 Wiley Periodicals, Inc.     

Wolbachia infections in the Cimicidae: museum specimens as an untapped resource for endosymbiont surveys

Wolbachia spp. are obligate maternally inherited endosymbiotic bacteria that infect diverse arthropods and filarial nematodes. Previous microscopic and molecular studies have identified Wolbachia in several bed bug species (Cimicidae), but little is known about how widespread Wolbachia infections are among the Cimicidae. Because cimicids of non-medical importance are not commonly collected, we hypothesized that preserved museum specimens could be assayed for Wolbachia infections. For the screening of museum specimens, we designed a set of primers that specifically amplify small diagnostic fragments (130 to 240 bp) of the Wolbachia 16S rRNA gene. Using these and other previously published primers, we screened 39 cimicid species (spanning 16 genera and all 6 recognized subfamilies) and 2 species of the sister family Polyctenidae for Wolbachia infections using museum and wild-caught material. Amplified fragments were sequenced to confirm that our primers were amplifying Wolbachia DNA. We identified 10 infections, 8 of which were previously undescribed. Infections in the F supergroup were common in the subfamily Cimicinae, while infections in the A supergroup were identified in the subfamilies Afrocimicinae and Haematosiphoninae. Even though specimens were degraded, we detected infections in over 23% of cimicid species. Our results indicate that Wolbachia infections may be common among cimicids and that archived museum material is a useful untapped resource for invertebrate endosymbiont surveys. The new screening primers listed in this report will be useful for other researchers conducting Wolbachia surveys with specimens with less-than-optimum DNA quality.     

Microbial enhancement of crop resource use efficiency

Naturally occurring soil microbes may be used as inoculants to maintain crop yields despite decreased resource (water and nutrient) inputs. Plant symbiotic relationships with mycorrhizal fungi alter root aquaporin gene expression and greatly increase the surface area over which plant root systems take up water and nutrients. Soil bacteria on the root surface alter root phytohormone status thereby increasing growth, and can make nutrients more available to the plant. Combining different classes of soil organism within one inoculant can potentially take advantage of multiple plant growth-promoting mechanisms, but biological interactions between inoculant constituents and the plant are difficult to predict. Whether the yield benefits of such inocula allow modified nutrient and water management continues to challenge crop biotechnologists.     

Microbial inefficient substrate use through the perspective of resource allocation models

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Microbial cultivation and the role of microbial resource centers in the omics era

Despite tremendous advances in microbial ecology over the past two decades, traditional cultivation methods have failed to grow ecologically more relevant microorganisms in the laboratory, leading to a predominance of weed-like species in the world’s culture collections. In this review, we highlight the gap between culture-based and culture-independent methods of microbial diversity analysis, especially in investigations of slow growers, oligotrophs, and fastidious and recalcitrant microorganisms. Furthermore, we emphasize the importance of microbial cultivation and the acquisition of the cultivation-based phenotypic data for the testing of hypotheses arising from genomics and proteomics approaches. Technical difficulties in cultivating novel microorganisms and how modern approaches have helped to overcome these limitations are highlighted. After cultivation, adequate preservation without changes in genotypic and phenotypic features of these microorganisms is necessary for future research and training. Hence, the contribution of microbial resource centers in the handling, preservation, and distribution of this novel diversity is discussed. Finally, we explore the concept of microbial patenting and requisite guidelines of the “Budapest Treaty” for establishment of an International Depositary Authority.     

Symbiotic microorganisms: untapped resources for insect pest control

Symbiotic microorganisms offer one route to meet the anticipated heightened demand for novel insect pest management strategies created by growing human populations and global climate change. Two approaches have particular potential: the disruption of microbial symbionts required by insect pests, and manipulation of microorganisms with major impacts on insect traits contributing to their pest status (e.g. capacity to vector diseases, natural enemy resistance). Specific research priorities addressed in this article include identification of molecular targets against which highly specific antagonists can be designed or discovered, and management strategies to manipulate the incidence and properties of facultative microorganisms that influence insect pest traits. Collaboration with practitioners in pest management will ensure that the research agenda is married to agricultural and public health needs.     

Siberian plants: untapped repertoire of bioactive endosymbionts

Background

Endosymbionts are microorganisms present in all plant species, and constitute the subject of interest among the scientific community. These symbionts have gained considerable attention in recent years, owing to their emerging biological roles. Global challenges, such as antimicrobial resistance, treatment of infectious diseases such as HIV and tuberculosis, cancer, and many genetic disorders, exist. Endosymbionts can help address these challenges by secreting valueadded bioactive compounds with various activities.

Objective

Herein, we describe the importance of plants inhabiting Siberian niches. These plants are considered to be among the least studied organisms in the plant kingdom worldwide. Barcoding these plants can be of interest for exploring bioactive endosymbionts possessing myriad biological properties.

Methods

A systematic survey of relevant scientific reports was conducted using the PubMed search engine. The reports were analyzed, and compiled to draft this review.

Results

The literature survey on Siberian plants regarding endosymbionts included a few reports, since extremely few exploratory studies have been conducted on the plants in these regions. Studies on the endosymbionts of these plants are highly valuable, as they report potent endosymbionts possessing numerous biological properties. Based on these considerations, this review aims to create awareness among the global scientific community working on related areas.

Conclusion

This review could provide the basis for barcoding novel endosymbionts of Siberian plants and their ecological importance, which can be exploited in various sectors. The main purpose of this review is to create awareness of Siberian plants, which are among the least studied organisms in the plant kingdom, with respect to endosymbionts, among the scientific community.

     

Marine microorganisms as an untapped source of bioactive compounds

The search for novel biologically active molecules has extended to the screening of organisms associated with less explored environments. In this sense, Oceans, which cover nearly the 67% of the globe, are interesting ecosystems characterized by a high biodiversity that is worth being explored. As such, marine microorganisms are highly interesting as promising sources of new bioactive compounds of potential value to humans. Some of these microorganisms are able to survive in extreme marine environments and, as a result, they produce complex molecules with unique biological interesting properties for a wide variety of industrial and biotechnological applications. Thus, different marine microorganisms (fungi, myxomycetes, bacteria, and microalgae) producing compounds with antioxidant, antibacterial, apoptotic, antitumoral and antiviral activities have been already isolated. This review compiles and discusses the discovery of bioactive molecules from marine microorganisms reported from 2018 onwards. Moreover, it highlights the huge potential of marine microorganisms for obtaining highly valuable bioactive compounds.     

The Amaryllidaceae alkaloids: an untapped source of acetylcholinesterase inhibitors

Phytochemistry Reviews - The AChE inhibitory activity of alkaloid extracts and compounds has been in the focus of research on the plants of Amaryllidoideae subfamily since the approval of...     

Microbial resource allocation for phosphatase synthesis reflects the availability of inorganic phosphorus across various soils

According to the resource allocation model for extracellular enzyme synthesis, microorganisms should preferentially allocate their resources to phosphorus (P)-acquiring enzyme synthesis when P availability is low in soils. However, the validity of this model across different soil types and soils differing in their microbial community composition has not been well demonstrated. Here we investigated whether the resource allocation model for phosphatase synthesis is applicable across different soil types (Andosols, Acrisols, Cambisols, and Fluvisols) and land uses (arable and forest), and we examined which soil test P and/or P fraction microorganisms responded to when investing their resources in phosphatase synthesis in the soils. The ratio of alkaline phosphatase (ALP) to β-d-glucosidase (BG) activities in the arable soils and the ratio of acid phosphatase (ACP) to BG activities in the forest soils were significantly negatively related with the available inorganic P concentration. We also observed significant effects of available inorganic P, pH, soil types, and land uses on the (ACP + ALP)/BG ratio when the data for the arable and forest soils were combined and used in a stepwise multiple regression analysis. These results suggest that microbial resource allocation for phosphatase synthesis is primarily controlled by available inorganic P concentration and soil pH, but the effects of soil types and land uses are also significant.     

Bioactive lichen metabolites: alpine habitats as an untapped source

Lichens are fungal and algal/cyanobacterial symbioses resulting in the production of specific metabolites. Some of these are forming an available biomass for phytochemical investigations, including the assessment of biological activities of the isolated compounds. The alpine or polar region are characterised by highly stressful environmental conditions for many organisms, but lichens are among the dominating organisms in these habitats. In the performant mutual protective system, lichen fungi often accumulate high amounts of metabolites with specific physicochemical properties (UV absorbents, hydrophobicity) which help the lichens to survive. Unique secondary metabolites and polysaccharides have been isolated and tested from these organisms. Even though this has been tested until now only with a low number of compounds so far, interesting activities have been recorded. We review here some of the antimicrobial, anti-inflammatory, antiproliferative and antioxidant activities properties described. Solutions with axenic biotechnological cultivation of each symbiotic partner and particularly the mycobiont to obtain the lichen secondary metabolites are challenging to overcome the limitations for the supply of these rare compounds. Additionally, these lichens appear to harbour a diversity of culturable microorganisms from which active compounds have also been isolated recently.     

Rat Phenome Project: the untapped potential of existing rat strains.

The National Bio Resource Project for the Rat in Japan collects, preserves, and distributes rat strains. More than 250 inbred strains have been deposited thus far into the National Bio Resource Project for the Rat and are maintained as specific pathogen-free rats or cryopreserved embryos. We are now comprehensively characterizing deposited strains as part of the Rat Phenome Project to reevaluate their value as models of human diseases. Phenotypic data are being collected for 7 categories and 109 parameters: functional observational battery (neurobehavior), behavior studies, blood pressure, biochemical blood tests, hematology, urology, and anatomy. Furthermore, genotypes are being determined for 370 simple sequence-length polymorphism markers distributed through the whole rat genome. Here, we report these large-scale, high-throughput screening data that have already been collected for 54 rat strains. This comprehensive, original phenotypic data can be systematically viewed by "strain ranking" for each parameter. This allows investigators to explore the relationship between several rat strains, to identify new rat models, and to select the most suitable strains for specific experiments. The discovery of several potential models for human diseases, such as hypertension, hypotension, renal diseases, hyperlipemia, hematological disorders, and neurological disorders, illustrates the potential of many existing rat strains. All deposited strains and obtained data are freely available for any interested researcher worldwide at http://www.anim.med.kyoto-u.ac.jp/nbr.