Search results for "bacteri"

Production of extracellular fructans by Gluconobacter nephelii P1464.

2015

UNLABELLED Bacterial extracellular fructans, known as levans, have potential applications in food, pharmaceutical and cosmetic industries and high fructan producing strains could contribute into the cost reduction and more extensive commercial usage of them. An acetic acid bacteria (AAB) isolate P1464 was obtained from the Microbial Strain Collection of Institute of Microbiology and Biotechnology, University of Latvia and identified as Gluconobacter nephelii by DNA-DNA hybridization and the formation of extracellular fructans by this strain was confirmed. Isolated extracellular fructose polymers were characterized using FT-IR spectroscopy and the structural features of fructan appeared as s…

Influence of salt of different origin on the microbiological characteristics, histamine generation and volatile profile of salted anchovies (Engrauli…

2018

Abstract The effect of six salts of different geographical areas on the quality of salted anchovies was evaluated. The crude salts were chemically characterized by determination of inorganic and volatile organic compounds (VOCs). Salted anchovies, corresponding to six experimental trials, were subjected to microbiological, chemical (including histamine content) and sensory analysis during the entire period of ripening (150 days). The salts were characterized by marked differences in terms of major cations and trace element amounts. Among the 27 VOCs detected, octadecane was the most abundant compound and the main differences of the salts were registered for alkanes and alcohols. During matu…

Susceptibility of Grapholita molesta (Busck, 1916) to formulations of Bacillus thuringiensis, individual toxins and their mixtures.

2016

The Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of fruit trees worldwide, such as peach and apple. Bacillus thuringiensis has been shown to be an efficient alternative to synthetic insecticides in the control of many agricultural pests. The objective of this study was to evaluate the effectiveness of B. thuringiensis individual toxins and their mixtures for the control of G. molesta. Bioassays were performed with Cry1Aa, Cry1Ac, Cry1Ca, Vip3Aa, Vip3Af and Vip3Ca, as well as with the commercial products DiPel® and XenTari®. The most active proteins were Vip3Aa and Cry1Aa, with LC50 values of 1.8 and 7.5ng/cm2, respectively. Vip3Ca was nontoxic to this …

Cryptogams signify key transitions of bacteria and fungi in Arctic sand dune succession.

2020

•Primary succession models focus on aboveground vascular plants. However, the prevalence of mosses and lichens, i.e. cryptogams, suggests they play a role in soil successions. Here, we explore whether effects of cryptogams on belowground microbes can facilitate progressive shifts in sand dune succession. •We linked aboveground vegetation, belowground bacterial and fungal communities, and soil chemical properties in six successional stages in Arctic inland sand dunes: bare sand, grass, moss, lichen, ericoid heath and mountain birch forest. •Compared to the bare sand and grass stages, microbial biomass and the proportion of fungi increased in the moss stage, and later stage microbial groups a…

The IM30/Vipp1 C-terminus associates with the lipid bilayer and modulates membrane fusion.

2017

IM30/Vipp1 proteins are crucial for thylakoid membrane biogenesis in chloroplasts and cyanobacteria. A characteristic C-terminal extension distinguishes these proteins from the homologous bacterial PspA proteins, and this extension has been discussed to be key for the IM30/Vipp1 activity. Here we report that the extension of the Synechocystis IM30 protein is indispensable, and argue that both, the N-terminal PspA-domain as well as the C-terminal extension are needed in order for the IM30 protein to conduct its in vivo function. In vitro, we show that the PspA-domain of IM30 is vital for stability/folding and oligomer formation of IM30 as well as for IM30-triggered membrane fusion. In contra…

Rapid dissemination of Mycobacterium bovis from cattle dung to soil by the earthworm Lumbricus terrestris

2016

International audience; Indirect transmission of Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), between wildlife and livestock is thought to occur by inhalation or ingestion of environmental substrates contaminated through animal shedding. The role of the soil fauna, such as earthworms, in the circulation of M. bovis from contaminated animal feces is of interest in the epidemiology of bTB. The objective of this study was to assess the impact of earthworm activity on M. bovis transfer from animal dung to castings and the surrounding soil. For this purpose, microcosms of soil containing the anecic eathworms Lumbricus terrestris were prepared and covered with cattle fec…

Gut microbiota of the pine weevil degrades conifer diterpenes and increases insect fitness

2017

AbstractThe pine weevil (Hylobius abietis), a major pest of conifer forests throughout Europe, feeds on the bark and cambium, tissues rich in terpenoid resins that are toxic to many insect herbivores. Here we report the ability of the pine weevil gut microbiota to degrade the diterpene acids of Norway spruce. The diterpene acid levels present in ingested bark were substantially reduced on passage through the pine weevil gut. This reduction was significantly less upon antibiotic treatment, and supplementing the diet with gut suspensions from untreated insects restored the ability to degrade diterpenes. In addition, cultured bacteria isolated from pine weevil guts were shown to degrade a Norw…

Shimia thalassica sp. nov., and reclassification of Pseudopelagicola gijangensis as Shimia gijangensis comb. nov., and Thalassobius activus as Cognat…

2019

Strain CECT 7735T, a marine Gram-reaction negative, aerobic, non-motile bacterium, was isolated from coastal seawater in Valencia, Spain. Strain CECT 7735T is chemoorganotrophic, mesophilic, slightly halophilic, grows at 15–28 °C but not at 4 or 37 °C, requires seawater for growth and grows up to 6 % salinity. The major cellular fatty acid is summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The G+C content of the genome is 55.7 mol%. Comparative analysis of the 16S rRNA gene sequence shows the strain is affiliated to the family Rhodobacteraceae , in the class Alphaproteobacteria , with highest similarities to Phaeobacter species (97.0–97.5 %), Shimia species (96.5–97.3 %) and Pseudopelagico…

2019

Hosts are typically infected with multiple strains or genotypes of one or several parasite species. These infections can take place simultaneously, but also at different times, i.e. sequentially, when one of the parasites establishes first. Sequential parasite dynamics are common in nature, but also in intensive farming units such as aquaculture. However, knowledge of effects of previous exposures on virulence of current infections in intensive farming is very limited. This is critical as consecutive epidemics and infection history of a host could underlie failures in management practices and medical intervention of diseases. Here, we explored effects of timing of multiple infections on vir…

Random Genetic Drift and Selective Pressures Shaping the Blattabacterium Genome

2018

AbstractEstimates suggest that at least half of all extant insect genera harbor obligate bacterial mutualists. Whereas an endosymbiotic relationship imparts many benefits upon host and symbiont alike, the intracellular lifestyle has profound effects on the bacterial genome. The obligate endosymbiont genome is a product of opposing forces: genes important to host survival are maintained through physiological constraint, contrasted by the fixation of deleterious mutations and genome erosion through random genetic drift. The obligate cockroach endosymbiont, Blattabacterium – providing nutritional augmentation to its host in the form of amino acid synthesis – displays radical genome alterations…