Comparative Study on Multiway Enhanced Bio- and Phytoremediation of Aged Petroleum-Contaminated Soil

Bioremediation and phytoremediation of soil polluted with petroleum hydrocarbons (PHs) are an e ective and eco-friendly alternative to physicochemical methods of soil decontamination. These techniques can be supported by the addition of e ective strains and/or surface-active compounds. However, to obtain maximum e cacy of bioremediation, the interactions that occur between the microorganisms, enhancement factors and plants need to be studied. Our study aimed to investigate the removal of petroleum hydrocarbons from an aged and highly polluted soil (hydrocarbon content about 2.5%) using multiway enhanced bio- and phytoremediation. For this purpose, 10 enhanced experimental groups were compared to two untreated controls. Among the enhanced experimental groups, the bio- and phytoremediation processes were supported by the endophytic strain Rhodococcus erythropolis CDEL254. This bacterial strain has several plant growth-promoting traits and can degrade petroleum hydrocarbons and produce biosurfactants. Additionally, a rhamnolipid solution produced by Pseudomonas aeruginosa was used to support the total petroleum hydrocarbon loss from soil. After 112 days of incubation, the highest PH removal (31.1%) was observed in soil planted with ryegrass (Lolium perenne L. cv. Pearlgreen) treated with living cells of the CDEL254 strain and rhamnolipid solution. For non-planted experimental groups, the highest PH loss (26.1%) was detected for soil treated with heat-inactivated CDEL254 cells and a rhamnolipid solution. In general, the di erences in the e cacy of the 10 experimental groups supported by plants, live/dead cells of the strain tested and rhamnolipid were not statistically significant. However, each of these groups was significantly more e ective than the appropriate control groups. The PH loss in untreated (natural attenuation) and soils that underwent phytoremediation reached a value of 14.2% and 17.4%, respectively. Even though the CDEL254 strain colonized plant tissues and showed high survival in soil, its introduction did not significantly increase PH loss compared to systems treated with dead biomass. These results indicate that the development of e ective biological techniques requires a customized approach to the polluted site and e ective optimization of the methods used

Analysis of the Genome of the Heavy Metal Resistant and Hydrocarbon-Degrading Rhizospheric Pseudomonas qingdaonensis ZCR6 Strain and Assessment of Its Plant-Growth- Promoting Traits

The Pseudomonas qingdaonensis ZCR6 strain, isolated from the rhizosphere of Zea mays growing in soil co-contaminated with hydrocarbons and heavy metals, was investigated for its plant growth promotion, hydrocarbon degradation, and heavy metal resistance. In vitro bioassays confirmed all of the abovementioned properties. ZCR6 was able to produce indole acetic acid (IAA), siderophores, and ammonia, solubilized Ca3(PO4)2, and showed surface active properties and activity of cellulase and very high activity of 1-aminocyclopropane-1-carboxylic acid deaminase (297 nmol α-ketobutyrate mg−1 h−1). The strain degraded petroleum hydrocarbons (76.52% of the initial hydrocarbon content was degraded) and was resistant to Cd, Zn, and Cu (minimal inhibitory concentrations reached 5, 15, and 10 mM metal, respectively). The genome of the ZCR6 strain consisted of 5,507,067 bp, and a total of 5055 genes were annotated, of which 4943 were protein-coding sequences. Annotation revealed the presence of genes associated with nitrogen fixation, phosphate solubilization, sulfur metabolism, siderophore biosynthesis and uptake, synthesis of IAA, ethylene modulation, heavy metal resistance, exopolysaccharide biosynthesis, and organic compound degradation. Complete characteristics of the ZCR6 strain showed its potential multiway properties for enhancing the phytoremediation of co-contaminated soils. To our knowledge, this is the first analysis of the biotechnological potential of the species P. qingdaonensis

Enzymy uczestniczące w biodegradacji polimerów

Most widely used plastics are considered to be resistant to environmental factors. Degradation of most popular packaging polymer is slow and may take hundreds of years. To enhance their environmental degradation, a number of different approaches, among them copolymerisation or compounding with additives susceptible to environmental factors such as polyesters are used. Enzymes involved in decomposition of polyesters are mainly hydrolases i.e. esterases, lipases, cutinases. The research team in the Department of Biochemistry is working on polyethylene and poly(ethylene terephtalate) films modified with synthetic aliphatic polyester Bionolle® and mechanisms of their biodegradation using fungal extracellular hydrolytic enzymes

Comparison of Two Inoculation Methods of Endophytic Bacteria to Enhance Phytodegradation Efficacy of an Aged Petroleum Hydrocarbons Polluted Soil

Endophyte-enhanced phytodegradation is a promising technology to clean up polluted soils. To improve the success rate of this nature-based remediation approach, it is important to advance the inoculation method as this has been shown to strongly affect the final outcome. However, studies evaluating inoculation strategies and their effect on hydrocarbon degradation are limited. This study aims to investigate two different manners of endophyte inoculation in Lolium perenne growing in an aged petroleum hydrocarbon polluted soil: (1) direct soil inoculation (SI), and (2) pre-inoculation of the caryopses followed by soil inoculation (PI). Different endophytic bacterial strains, Rhodococcus erythropolis 5WK and Rhizobium sp. 10WK, were applied individually as well as in combination. Depending on the method of inoculation, the petroleum hydrocarbon (PHC) degradation potential was significantly different. The highest PHC removal was achieved after pre-inoculation of ryegrass caryopses with a consortium of both bacterial strains. Moreover, both strains established in the aged-polluted soil and could also colonize the roots and shoots of L. perenne. Importantly, used endophytes showed the selective colonization of the environment compartments. Our findings show that the method of inoculation determines the effciency of the phytodegradation process, especially the rate of PHC degradation. This study provides valuable information for choosing the most cost-effective and beneficial means to optimize phytodegradation

Mutation in HvCBP20 (Cap binding protein 20) adapts barley to drought stress at phenotypic and transcriptomic levels

This work was supported by the European Regional Development Fund through the Innovative Economy for Poland 2007–2013, project WND-POIG.01.03.01-00-101/08 POLAPGEN-BD “Biotechnological tools for breeding cereals with increased resistance to drought,” task 22; National Science Centre, Poland, project SONATA 2015/19/D/NZ9/03573 “Translational genomics approach to identify the mechanisms of CBP20 signalosome in Arabidopsis and barley under drought stress.”CBP20 (Cap-Binding Protein 20) encodes a small subunit of the cap-binding complex (CBC), which is involved in the conserved cell processes related to RNA metabolism in plants and, simultaneously, engaged in the signaling network of drought response, which is dependent on ABA. Here, we report the enhanced tolerance to drought stress of barley mutant in the HvCBP20 gene manifested at the morphological, physiological, and transcriptomic levels. Physiological analyses revealed differences between the hvcbp20.ab mutant and its WT in response to a water deficiency. The mutant exhibited a higher relative water content (RWC), a lower stomatal conductance and changed epidermal pattern compared to the WT after drought stress. Transcriptome analysis using the Agilent Barley Microarray integrated with observed phenotypic traits allowed to conclude that the hvcbp20.ab mutant exhibited better fitness to stress conditions by its much more efficient and earlier activation of stress-preventing mechanisms. The network hubs involved in the adjustment of hvcbp20.ab mutant to the drought conditions were proposed. These results enabled to make a significant progress in understanding the role of CBP20 in the drought stress response.European Regional Development Fund; National Science Centre, Polan

Multi-omics insights into the positive role of strigolactone perception in barley drought response

BACKGROUND: Drought is a major environmental stress that affects crop productivity worldwide. Although previous research demonstrated links between strigolactones (SLs) and drought, here we used barley (Hordeum vulgare) SL-insensitive mutant hvd14 (dwarf14) to scrutinize the SL-dependent mechanisms associated with water deficit response. RESULTS: We have employed a combination of transcriptomics, proteomics, phytohormonomics analyses, and physiological data to unravel differences between wild-type and hvd14 plants under drought. Our research revealed that drought sensitivity of hvd14 is related to weaker induction of abscisic acid-responsive genes/proteins, lower jasmonic acid content, higher reactive oxygen species content, and lower wax biosynthetic and deposition mechanisms than wild-type plants. In addition, we identified a set of transcription factors (TFs) that are exclusively drought-induced in the wild-type barley. CONCLUSIONS: Critically, we resolved a comprehensive series of interactions between the drought-induced barley transcriptome and proteome responses, allowing us to understand the profound effects of SLs in alleviating water-limiting conditions. Several new avenues have opened for developing barley more resilient to drought through the information provided. Moreover, our study contributes to a better understanding of the complex interplay between genes, proteins, and hormones in response to drought, and underscores the importance of a multidisciplinary approach to studying plant stress response mechanisms

Additional file 1 of Multi-omics insights into the positive role of strigolactone perception in barley drought response

Additional file 1: Supplemental Figures, Supplemental Figure 1. Treatment with synthetic SL analogue (GR245DS) confirmed SL-insensitivity of hvd14. A. 18-day-old seedlings of both genotypes treated with 10 µM GR245DS or control solution (0.01% acetone). B. Effect of GR245DS treatment on barley branching. Bars represent the mean ±SE (n=32). Asterisks indicate significant differences as determined by Student’s t-test (***P≤0.001).  Supplemental Figure 2. Plant survival of WT and hvd14. A. Overview of the experimental setup: in the single pot 15 seedlings of each genotype were grown together. B. The phenotype of plants after 15 days without watering and three additional days with re-watering. C. Plant survival of both genotypes. Bars represent the mean ±SE (n=120). Asterisks indicate significant differences as determined by Student’s t-test (***P≤0.001). Supplemental Figure 3. Overview of differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) identified in the present work. Supplemental Figure 4. Phytohormone-related genes and proteins differentially expressed in WT and hvd14 mutant, in response to drought. A. Number of ABA-related genes identified in both genotypes. B. Number of JA-related genes identified in both genotypes. C. Transcriptome and proteome data for compounds involved in JA biosynthesis, which were regulated by drought in both genotypes. D. Transcriptome and proteome data for compounds involved in CK signalling, which were regulated by drought in both genotypes

Additional file 3 of Multi-omics insights into the positive role of strigolactone perception in barley drought response

Additional file 3: Supplemental Data 2. Table S2a. List of up-regulated proteins in the WT_D vs WT_C comparison (log2FC ≥ 0.58, q-value ≤ 0.05). Table S2b. List of down-regulated proteins in the WT_D vs WT_C comparison (log2FC ≤ -0.58, q-value ≤ 0.05). Table S2c. List of up-regulated proteins in the hvd14_D vs hvd14_C comparison (log2FC ≥ 0.58, q-value ≤ 0.05). Table S2d. List of down-regulated proteins in the hvd14_D vs hvd14_C comparison (log2FC ≤ -0.58, q-value ≤ 0.05). Table S2e. List of proteins up-regulated by drought, only in WT (log2FC ≥ 0.58, q-value ≤ 0.05) - WT Drought Resposne Specific (WT DRS) proteins. Table S2f. List of proteins down-regulated by drought, only in WT (log2FC ≤ 0.58, q-value ≤ 0.05) - WT Drought Resposne Specific (WT DRS) proteins. Table S2g. List of proteins up-regulated by drought, only in hvd14 (log2FC ≥ 0.58, q-value ≤ 0.05) - hvd14 Drought Resposne Specific (hvd14 DRS) proteins. Table S2h. List of proteins down-regulated by drought, only in hvd14 (log2FC ≤ 0.58, q-value ≤ 0.05) - hvd14 Drought Resposne Specific (hvd14 DRS) proteins. Table S2i. List of proteins up-regulated by drought, in both genotypes: WT and hvd14 (log2FC ≥ 0.58, q-value ≤ 0.05). Table S2j. List of proteins down-regulated by drought, in both genotypes: WT and hvd14 (log2FC ≥ 0.58, q-value ≤ 0.05)

Additional file 8 of Multi-omics insights into the positive role of strigolactone perception in barley drought response

Additional file 8: Supplemental Data 7. Table S7a. Expression of genes described as crucial in wax biosynthesis (Daszkowska-Golec et al., 2020) or annotated to the ‘cutin biosynthetic process’ and ‘cuticle development’ induced by drought in WT and/or hvd14. Table S7b. The analyses of epicuticular waxes in WT and hvd14 under control (C) and drought (D) conditions (µg/g dry weight)