Extremophile
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Halophilic bacteria are extremophiles that thrive in saline environment. Their ability to withstand such harsh conditions makes them an ideal choice for industrial applications such as lignocellulosic biomass degradation. In this study, a halophilic bacterium with the ability to produce extracellular cellulases and hemicellulases, designated as Nesterenkonia sp. CL21, was isolated from mangrove sediment in Tanjung Piai National Park, Malaysia. Thus far, studies on lignocellulolytic enzymes concerning bacterial species under this genus are limited. To gain a comprehensive understanding of its lignocellulose-degrading potential, the whole genome was sequenced using the Illumina NovaSeq 6000 platform. The genome of strain CL21 was assembled into 25 contigs with 3,744,449 bp and a 69.74% GC content and was predicted to contain 3,348 coding genes. Based on taxonomy analysis, strain CL21 shares 73.8 to 82.0% average nucleotide identity with its neighbouring species, below the 95% threshold, indicating its possible status as a distinct species in Nesterenkonia genus. Through in-depth genomic mining, a total of 81 carbohydrate-active enzymes were encoded. Among these, 24 encoded genes were identified to encompass diverse cellulases (GH3), xylanases (GH10, GH11, GH43, GH51, GH127 and CE4), mannanases (GH38 and GH106) and pectinases (PL1, PL9, and PL11). The production of lignocellulolytic enzymes was tested in the presence of several substrates. This study revealed that strain CL21 can produce a diverse array of enzymes which are active at different time points. By combining experimental data with genomic information, the ability of strain CL21 to produce lignocellulolytic enzymes has been elucidated, with potential applications in biorefinery industry.
- MeSH
- bakteriální proteiny genetika metabolismus MeSH
- celulasy genetika metabolismus MeSH
- fylogeneze * MeSH
- genom bakteriální * MeSH
- genomika * MeSH
- geologické sedimenty mikrobiologie MeSH
- glykosidhydrolasy * genetika metabolismus MeSH
- lignin * metabolismus MeSH
- RNA ribozomální 16S genetika MeSH
- sekvenování celého genomu MeSH
- zastoupení bazí MeSH
- Publikační typ
- časopisecké články MeSH
The paper reports a low-cost handheld source of a cold air plasma intended for biomedical applications that can be made by anyone (detailed technical information and a step-by-step guide for creating the NTP source are provided). The plasma source employs a 1.4 W corona discharge in the needle-to-cone electrode configuration and is an extremely simple device, consisting basically of two electrodes and a cheap power supply. To achieve the best bactericidal effect, the plasma source has been optimized on Escherichia coli. The bactericidal ability of the plasma source was further tested on a wide range of microorganisms: Staphylococcus aureus as a representative of gram-positive bacteria, Pseudomonas aeruginosa as gram-negative bacteria, Candida albicans as yeasts, Trichophyton interdigitale as microfungi, and Deinococcus radiodurans as a representative of extremophilic bacteria resistant to many DNA-damaging agents, including ultraviolet and ionizing radiation. The testing showed that the plasma source inactivates all the microorganisms tested in several minutes (up to 105-107 CFU depending on a microorganism), proving its effectiveness against a wide spectrum of pathogens, in particular microfungi, yeasts, gram-positive and gram-negative bacteria. Studies of long-lived reactive species such as ozone, nitrogen oxides, hydrogen peroxide, nitrite, and nitrate revealed a strong correlation between ozone and the bactericidal effect, indicating that the bactericidal effect should generally be attributed to reactive oxygen species. This is the first comprehensive study of the bactericidal effect of a corona discharge in air and the formation of long-lived reactive species by the discharge, depending on both the interelectrode distance and the discharge current.
Purple photosynthetic bacteria (PPB) are versatile microorganisms capable of producing various value-added chemicals, e.g., biopolymers and biofuels. They employ diverse metabolic pathways, allowing them to adapt to various growth conditions and even extreme environments. Thus, they are ideal organisms for the Next Generation Industrial Biotechnology concept of reducing the risk of contamination by using naturally robust extremophiles. Unfortunately, the potential of PPB for use in biotechnology is hampered by missing knowledge on regulations of their metabolism. Although Rhodospirillum rubrum represents a model purple bacterium studied for polyhydroxyalkanoate and hydrogen production, light/chemical energy conversion, and nitrogen fixation, little is known regarding the regulation of its metabolism at the transcriptomic level. Using RNA sequencing, we compared gene expression during the cultivation utilizing fructose and acetate as substrates in case of the wild-type strain R. rubrum DSM 467T and its knock-out mutant strain that is missing two polyhydroxyalkanoate synthases PhaC1 and PhaC2. During this first genome-wide expression study of R. rubrum, we were able to characterize cultivation-driven transcriptomic changes and to annotate non-coding elements as small RNAs.
- Publikační typ
- časopisecké články MeSH
In recent years, extremophilic microorganisms have been employed as producers of the microbial bioplastics polyhydroxyalkanoates (PHA), which are of great biotechnological value. Nevertheless, cold-loving or psychrophilic (cryophilic) bacteria have been neglected in this regard. Here, we present an investigation of the Arctic glacier-derived PHA producer Acidovorax sp. A1169. Biolog GEN III Microplates were used as a screening tool to identify the most suitable carbon substrate concerning PHA synthesis. The strain produced homopolymer poly(3-hydroxybutyrate) (PHB) most efficiently (2 g/L) at a temperature of 15 °C when supplied with fructose or mannitol as carbon sources with a substantial decrease of PHB biosynthesis at 17.5 °C. The PHB yield did not increase considerably or even decreased when carbon source concentration exceeded 10 g/L hinting that the strain is oligotrophic in nature. The strain was also capable of introducing 3-hydroxyvalerate (3HV) into the polymer structure, which is known to improve PHA thermoplastic properties. This is the first investigation providing insight into a PHA biosynthesis process by means of a true psychrophile, offering guidelines on polar-region bacteria cultivation, production of PHA and also on the methodology for genetic engineering of psychrophiles.
- MeSH
- Comamonadaceae * genetika MeSH
- genetické inženýrství MeSH
- polyhydroxyalkanoáty * MeSH
- teplota MeSH
- uhlík MeSH
- Publikační typ
- časopisecké články MeSH
Biologická evoluce některých živých organismů by mohla přinést nový vhled do etiologie stárnutí. Organismy schopné odolat extrémním podmínkám jsou příklady dokonalé evoluce z hlediska biologické odolnosti: jejich genetická adaptace selekcí pomohla přeměnit nepřátelské prostředí na prostředí optimální. Když jsou extremofilní organismy Deinococcus radiodurans nebo Arthrobacter agilis vystaveny radiaci, mohou přejít ze stavu "klinické smrti" do procesu tzv. "vzkříšení" prostřednictvím sebeopravy. Bylo prokázáno, že stárnutí a nemoci související s věkem (ARD) sdílejí společnou hlavní příčinu: degradaci a poškození proteinů. Zejména karbonylované proteiny lze považovat za markery a akcelerátory stárnutí a ARD a to včetně Alzheimerovy a Parkinsonovy choroby, cukrovky, psoriázy a rakoviny kůže. Současný výzkum je velmi slibný a může otevřít nové terapeutické přístupy a perspektivy se zaměřením na ochranu proteomu.
The biological evolution of some living organisms is opening up a new path: understanding why and how we age. Organisms capable of withstanding extreme conditions are examples of perfect evolution in terms of biological robustness: their genetic adaptation by selection has helped transform a hostile environment into an optimal environment. When the extremophiles such as Deinococcus radiodurans or Arthrobacter agilis bacterias are exposed to radiation, they can transition from a "clinical death" state to a "resurrection" process through self-repair. It has been shown that ageing and age-related diseases (ARD) share the same cause: protein damage. Especially, protein carbonylation can be considered as marker and accelerator of ageing and it is common marker of most ARD including Alzheimer and Parkinson diseases, diabetes, psoriasis, and skin cancer. Current research is promising and may open new therapeutic approaches and perspectives by targeting proteome protection.
- MeSH
- dlouhověkost * fyziologie MeSH
- karbonylace proteinů fyziologie MeSH
- lidé MeSH
- molekulární chaperony fyziologie MeSH
- proteolýza MeSH
- proteom fyziologie MeSH
- stárnutí kůže * fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Resistance to adverse conditions is widespread in the microbial world. Microorganisms resistant to ionizing radiation form a technologically interesting but little-explored group. This work focuses on the mechanisms of resistance to radiation in representatives of the Actinobac-teria phylum, both in terms of detoxification mechanisms and in terms of repairing DNA damage.
In this work, the mesophilic bacterium Burkholderia sacchari, the halophilic bacterium Halomonas halophila, and the thermophilic bacterium Schlegelella thermodepolymerans were evaluated with regards to their suitability for polyhydroxyalkanoates (PHA) production from model media mimicking lignocellulose hydrolysates. B. sacchari was capable of utilizing all the tested "model hydrolysates", yielding comparable PHA titers and turning out as very robust against lignocellulose-derived microbial inhibitors. On the contrary, H. halophila reached substantially higher PHA titers on hexoses-rich media, while S. thermodepolymerans preferred media rich in pentoses. Both extremophiles were more sensitive to microbial inhibitors than B. sacchari. Nevertheless, considering substantially higher PHA productivity of both extremophiles even in the presence of microbial inhibitors and also other positive factors associated with utilization of extremophiles, such as the reduced risk of microbial contamination, both H. halophila and S. thermodepolymerans are auspicious candidates for sustainable PHA production from abundantly available, inexpensive lignocelluloses.
- MeSH
- Burkholderiaceae MeSH
- Comamonadaceae MeSH
- Halomonas * MeSH
- lignin MeSH
- polyhydroxyalkanoáty * MeSH
- Publikační typ
- časopisecké články MeSH
Amylases and proteases are among the industrially most important enzymes for food processing, animal feed, brewing, starch processing, detergents, healthcare, leather processing, and biofuel production. In this study, we investigated the growth kinetics and statistically optimized the co-production of amylase and protease in a phylogenetically novel haloalkaliphilic actinomycete, Streptomyces lopnurensis KaM5 of seawater. The Plackett-Berman design using Minitab 14.0 software was employed to assess the impact of the nutritional factors, temperature, pH, and incubation time. Further, starch, yeast extract, NaCl concentrations, and incubation time were optimized by Box-Behnken design at their three levels. The Pareto charts, contour, surface plots, and individual factorial analysis expressed the variability and levels for the optimal enzyme production. ANOVA analysis admitted the statistical fitness and significance level among the variables. A two-fold increase in enzyme production was achieved by cost-effective co-production media. The study was further extended to growth kinetics associated with enzyme production. Specific growth rate (μ), maximal cell mass (Xmax), volumetric product formation (Pmax), rate of product formation (Qp), and generation time (g) were computed and analyzed. These parameters significantly improved when compared with the pre-optimized conditions, and the production economics of the enzyme was industrially viable. The initial studies on the characteristics of the enzymes suggested its ability to function under the combination of alkaline pH and high salt concentrations. The co-production of enzymes from extremophiles can be a potentially viable option for large-scale production and applications.
Polyhydroxyalkanoates are microbial polyesters which are considered being biological alternatives to petrochemical polymers. Extremophiles, such as thermophilic PHA producers, hold promise to improve competitiveness of PHA production process. Therefore, this work aimed at isolation of new strains, which could produce PHA under elevated temperature. Since traditional Nile red staining of colonies provided false positive results in thermophiles, we developed a novel strategy of enriching microbial consortia by PHA producers. This so called "osmoselective strategy" is based on application of osmotic challenge by sudden exposition of the mixed microbial culture to hypertonic and subsequently to hypotonic conditions; moreover, this strategy relies on the fact that PHA protect bacteria from negative effects of rapid fluctuations in osmotic pressure. In combination with fast and reliable ATR-FTIR inspection of selected colonies for presence of PHA, we were able to isolate several promising thermophilic or thermotolerant PHA producing strains belonging to the genera Bacillus, Aneurinibacillus and Chelatococcus, which indeed deserves further investigation to evaluate their potential for industrial production of PHA.
- MeSH
- Alphaproteobacteria izolace a purifikace MeSH
- Bacillales izolace a purifikace MeSH
- Bacillus izolace a purifikace MeSH
- Bacteria izolace a purifikace MeSH
- bioreaktory MeSH
- DNA bakterií MeSH
- fermentace MeSH
- mikrobiální společenstva * MeSH
- osmóza MeSH
- polyhydroxyalkanoáty chemie MeSH
- sekvence nukleotidů MeSH
- termotolerance MeSH
- vysoká teplota MeSH
- Publikační typ
- časopisecké články MeSH
Pseudomonas prosekii is a recently described species isolated exclusively from James Ross Island close to the Antarctic Peninsula at 64° south latitude. Here, we present two P. prosekii genome sequences and their analyses with respect to phylogeny, low temperature adaptation, and potential biotechnological applications. The genome of P. prosekii P2406 comprised 5,896,482 bp and 5324 genes (GC content of 59.71%); the genome of P. prosekii P2673 consisted of 6,087,670 bp and 5511 genes (GC content of 59.50%). Whole genome sequence comparisons confirmed a close relationship between both investigated strains and strain P. prosekii LMG 26867T. Gene mining revealed the presence of genes involved in stress response, genes encoding cold shock proteins, oxidative stress proteins, osmoregulation proteins, genes for the synthesis of protection molecules, and siderophores. Comparative genome analysis of P. prosekii and P. aeruginosa PAO1 highlighted differences in genome content between extremophile species and a mesophilic opportunistic pathogen.
- MeSH
- aklimatizace MeSH
- bakteriální proteiny genetika MeSH
- fylogeneze MeSH
- fyziologická adaptace MeSH
- genom bakteriální * MeSH
- mapování chromozomů MeSH
- nadmořská výška MeSH
- Pseudomonas genetika izolace a purifikace fyziologie MeSH
- sekvence nukleotidů MeSH
- sekvenování celého genomu MeSH
- zastoupení bazí MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Antarktida MeSH
