Secondary compound hypothesis revisited: Selected plant secondary metabolites promote bacterial degradation of cis-1,2-dichloroethylene (cDCE)

AbstractCis-1,2-dichloroethylene (cDCE), which is a common hazardous compound, often accumulates during incomplete reductive dechlorination of higher chlorinated ethenes (CEs) at contaminated sites. Simple monoaromatics, such as toluene and phenol, have been proven to induce biotransformation of cDCE in microbial communities incapable of cDCE degradation in the absence of other carbon sources. The goal of this microcosm-based laboratory study was to discover non-toxic natural monoaromatic secondary plant metabolites (SPMEs) that could enhance cDCE degradation in a similar manner to toluene and phenol. Eight SPMEs were selected on the basis of their monoaromatic molecular structure and widespread occurrence in nature. The suitability of the SPMEs chosen to support bacterial growth and to promote cDCE degradation was evaluated in aerobic microbial cultures enriched from cDCE-contaminated soil in the presence of each SPME tested and cDCE. Significant cDCE depletions were achieved in cultures enriched on acetophenone, phenethyl alcohol, p-hydroxybenzoic acid and trans-cinnamic acid. 16S rRNA gene sequence analysis of each microbial community revealed ubiquitous enrichment of bacteria affiliated with the genera Cupriavidus, Rhodococcus, Burkholderia, Acinetobacter and Pseudomonas. Our results provide further confirmation of the previously stated secondary compound hypothesis that plant metabolites released into the rhizosphere can trigger biodegradation of environmental pollutants, including cDCE.</jats:p

Clinical Case of Complicated Thrombophilia in a Patient with Ulcerative Colitis

This article presents the clinical observation of hereditary thrombophilia, complicated by the formation of a thrombus in the cavity of the right ventricle, in a 40-year-old patient with first diagnosed ulcerative colitis. Despite the standard drug therapy, the patient had a persistent fever. Transthoracic echocardiogram revealed a formation in the right ventricle. A differential diagnosis was made between the vegetation and thrombus. Due to the high risk of infective endocarditis, the antibacterial therapy was started. The addition of deep vein and common iliac vein thrombosis required the exclusion of thrombophilia. Molecular genetic testing allowed to diagnose hereditary thrombophilia: heterozygous carriage of mutations in the genes of factor V Leiden, fibrinogen, platelet receptor for collagen, plasminogen activator inhibitor I. The diagnosis of thrombophilia and ineffectiveness of antibacterial therapy led to the conclusion that there was a thrombus in the right ventricle. The treatment of ulcerative colitis was continued. At the same time, anticoagulant therapy was started, and antibiotics were canceled. As a result, clinical remission of ulcerative colitis, regression of venous thrombosis and complete dissolution of the thrombus in the cavity of the right ventricle were achieved. Ulcerative colitis may be complicated by venous trombosis and hereditary thrombophilia increases this risk.</jats:p

Clinical Case of Complicated Thrombophilia in a Patient with Ulcerative Colitis

This article presents the clinical observation of hereditary thrombophilia, complicated by the formation of a thrombus in the cavity of the right ventricle, in a 40-year-old patient with first diagnosed ulcerative colitis. Despite the standard drug therapy, the patient had a persistent fever. Transthoracic echocardiogram revealed a formation in the right ventricle. A differential diagnosis was made between the vegetation and thrombus. Due to the high risk of infective endocarditis, the antibacterial therapy was started. The addition of deep vein and common iliac vein thrombosis required the exclusion of thrombophilia. Molecular genetic testing allowed to diagnose hereditary thrombophilia: heterozygous carriage of mutations in the genes of factor V Leiden, fibrinogen, platelet receptor for collagen, plasminogen activator inhibitor I. The diagnosis of thrombophilia and ineffectiveness of antibacterial therapy led to the conclusion that there was a thrombus in the right ventricle. The treatment of ulcerative colitis was continued. At the same time, anticoagulant therapy was started, and antibiotics were canceled. As a result, clinical remission of ulcerative colitis, regression of venous thrombosis and complete dissolution of the thrombus in the cavity of the right ventricle were achieved. Ulcerative colitis may be complicated by venous trombosis and hereditary thrombophilia increases this risk

Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

AbstractBackgroundThe N2-fixing cyanobacterium, Aphanizomenon flos-aquae is a globally distributed bloom causing species that degrades water quality of fresh and marine water bodies. Overcoming phosphorus (P) deficiency is one of the ecological advantages for bloom-forming cyanobacteria. It remains unclear to what extent can A. flos-aquae alleviate P deficiency by regulating P using strategies.ResultsBased on in situ observations of extracellular alkaline phosphatase (APase) in A. flos-aquae via enzyme-labeled fluorescence in freshwater bodies in China, Poland and Czechia, we further investigated responses of isolated A. flos-aquae to different P supplies (dissolved inorganic P (Pi) as +DIP, dissolved organic α-glycerophosphate and β-glycerophosphate as +DOPα and +DOPβ, P-free condition as P-depleted). The significantly negative relationships between percentage of APase producing cells and soluble reactive P concentration in both fields and cultures suggested that the excretion of APase in cyanobacterium was regulated by ambient Pi supply. Suffering from P deficiency in the P-depleted treatments, A. flos-aquae showed the highest APase activity but a vigorous growth at the early culture stage, which might also benefit from the formation of polyphosphate body (PPB) and the decrease of cell P quota. In the +DOP treatments, the coordination of dissolved DOP mineralization and continuous prompt utilization of PPB might contribute to a maintenance but not reproduction of A. flos-aquae when relying on DOP, since the specific growth rate kept around 0 cells L?1 day?1 at the second half culture period and the highest cell density reached only 13.38% of that in +DIP treatments while photochemical efficiency was comparable during the whole experiment. Luxury uptake of phosphate as PPB in the +DIP treatments was consistent to the canonical view of polyphosphate as P storage.ConclusionAphanizomenon flos-aquae could achieve an instantaneous growth in response to P deficiency with the coordination of P utilization strategies, while it maintained a long-term sustainable growth but not reproduction under sole DOP supply. Persistent and active reproduction could only be achieved in high Pi supply, which implying that an effective consequence can be expected for combating the bloom of A. flos-aquae when controlling P supply

Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

Abstract Background: The N2-fixing cyanobacterium, Aphanizomenon flos-aquae is a globally distributed bloom causing species that degrades water quality of freshwater and ocean worldwide. Overcoming phosphorus (P) deficiency is one of the ecological advantages for bloom forming cyanobacteria. It remains unclear to what extent can A. flos-aquae alleviate P deficiency by regulating P using strategies.Results: Based on in situ observations of extracellular alkaline phosphatase (APase) in A. flos-aquae via enzyme-labeled fluorescence in freshwater bodies in China, Poland and Czechia, we further investigated responses of isolated A. flos-aquae to different P supplies (sufficient inorganic P (Pi) as +DIP, α-glycerophosphate and β-glycerophosphate as +DOPα and +DOPβ, P-free condition as -P). The significantly negative relationships between percentage of APase producing cells and soluble reactive P concentration in fields and cultures respectively suggested that the excretion of APase was regulated by ambient Pi supply. Suffering from extreme P deficiency in the -P treatments, A. flos-aquae showed the highest APase activity reaching a vigorous growth at the early stage, which might also benefit from the formation of polyphosphate body (PPB) and the decrease of cellular P content. In the +DOP treatments, the coordination of dissolved organic P (DOP) mineralization and continuous utilization and formation of PPB might contribute to a maintenance but not reproduction of A. flos-aquae when relying on DOP, since the highest cell density reached only 13.38% of that in +DIP treatments while photochemical efficiency was comparable during the whole experiment. Luxury uptake of phosphate as PPB in the +DIP treatments was consistent to the canonical view of polyphosphate as P storage. Conclusion: A. flos-aquae could achieve an instantaneous growth in response to P deficiency with the coordination of P utilization strategies, while only a long-term sustainable growth could be maintained under DOP condition. Persistent and active reproduction could only be achieved in high Pi supply, which implying that an effective consequence can be expected for combating the bloom of A. flos-aquae when controlling P supply.</jats:p

Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

Abstract Background The N2-fixing cyanobacterium, Aphanizomenon flos-aquae is a globally distributed bloom causing species that degrades water quality of fresh and marine water bodies. Overcoming phosphorus (P) deficiency is one of the ecological advantages for bloom forming cyanobacteria. It remains unclear to what extent can A. flos-aquae alleviate P deficiency by regulating P using strategies. Results Based on in situ observations of extracellular alkaline phosphatase (APase) in A. flos-aquae via enzyme-labeled fluorescence in freshwater bodies in China, Poland and Czechia, we further investigated responses of isolated A. flos-aquae to different P supplies (dissolved inorganic P (Pi) as +DIP, dissolved organic α-glycerophosphate and β-glycerophosphate as +DOPα and +DOPβ, P-free condition as P-depleted). The significantly negative relationships between percentage of APase producing cells and soluble reactive P concentration in both fields and cultures suggested that the excretion of APase in cyanobacterium was regulated by ambient Pi supply. Suffering from P deficiency in the P-depleted treatments, A. flos-aquae showed the highest APase activity but a vigorous growth at the early culture stage, which might also benefit from the formation of polyphosphate body (PPB) and the decrease of cell P quota. In the +DOP treatments, the coordination of dissolved DOP mineralization and continuous prompt utilization of PPB might contribute to a maintenance but not reproduction of A. flos-aquae when relying on DOP, since the specific growth rate kept around 0 cells L-1 day-1 at the second half culture period and the highest cell density reached only 13.38% of that in +DIP treatments while photochemical efficiency was comparable during the whole experiment. Luxury uptake of phosphate as PPB in the +DIP treatments was consistent to the canonical view of polyphosphate as P storage. Conclusion A. flos-aquae could achieve an instantaneous growth in response to P deficiency with the coordination of P utilization strategies, while it maintained a long-term sustainable growth but not reproduction under sole DOP supply. Persistent and active reproduction could only be achieved in high Pi supply, which implying that an effective consequence can be expected for combating the bloom of A. flos-aquae when controlling P supply.</jats:p

Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

Abstract Background The N2-fixing cyanobacterium, Aphanizomenon flos-aquae is a globally distributed bloom causing species that degrades water quality of fresh and marine water bodies. Overcoming phosphorus (P) deficiency is one of the ecological advantages for bloom-forming cyanobacteria. It remains unclear to what extent can A. flos-aquae alleviate P deficiency by regulating P using strategies. Results Based on in situ observations of extracellular alkaline phosphatase (APase) in A. flos-aquae via enzyme-labeled fluorescence in freshwater bodies in China, Poland and Czechia, we further investigated responses of isolated A. flos-aquae to different P supplies (dissolved inorganic P (Pi) as +DIP, dissolved organic α-glycerophosphate and β-glycerophosphate as +DOPα and +DOPβ, P-free condition as P-depleted). The significantly negative relationships between percentage of APase producing cells and soluble reactive P concentration in both fields and cultures suggested that the excretion of APase in cyanobacterium was regulated by ambient Pi supply. Suffering from P deficiency in the P-depleted treatments, A. flos-aquae showed the highest APase activity but a vigorous growth at the early culture stage, which might also benefit from the formation of polyphosphate body (PPB) and the decrease of cell P quota. In the +DOP treatments, the coordination of dissolved DOP mineralization and continuous prompt utilization of PPB might contribute to a maintenance but not reproduction of A. flos-aquae when relying on DOP, since the specific growth rate kept around 0 cells L−1 day−1 at the second half culture period and the highest cell density reached only 13.38% of that in +DIP treatments while photochemical efficiency was comparable during the whole experiment. Luxury uptake of phosphate as PPB in the +DIP treatments was consistent to the canonical view of polyphosphate as P storage. Conclusion Aphanizomenon flos-aquae could achieve an instantaneous growth in response to P deficiency with the coordination of P utilization strategies, while it maintained a long-term sustainable growth but not reproduction under sole DOP supply. Persistent and active reproduction could only be achieved in high Pi supply, which implying that an effective consequence can be expected for combating the bloom of A. flos-aquae when controlling P supply. </jats:sec

Additional file 1 of Strategies adopted by Aphanizomenon flos-aquae in response to phosphorus deficiency and their role on growth

Additional file 1. Additional figures and table