Project description:Streptomyces sp. M7 has demonstrated ability to remove lindane from culture media and soils. In this study, we used MS-based label-free quantitative proteomic to understand lindane degradation and its metabolic context in Streptomyces sp. M7. We identified the proteins involved in the up-stream degradation pathway. Our results demonstrated that mineralization of lindane is feasible since proteins from an unusual down-stream degradation pathway were also identified. Degradative steps were supported by an active catabolism that supplied energy and reducing equivalents in the form of NADPH. This is the first study in which degradation steps of an organochlorine compound and metabolic context are elucidate in a biotechnological genus as Streptomyces. These results serve as basement to study other degradative actinobacteria and to improve the degradation processes of Streptomyces sp. M7.
Project description:This study is aimed to isolate marine actinomycetes from sediments from Andaman and the Gulf of Thailand. All 101 marine actinomycetes were screened for anti-biofilm activity. Streptomyces sp. GKU223 showed significantly inhibited biofilm formation of S. aureus. The evaluation of supernatants of anti-biofilm activity produced by Streptomyces sp. GKU223 has been performed. Since the interaction between marine actinomycetes and biofilm forming bacteria has never been investigated, proteomic analysis has been used to identify whole cell proteins involved in anti–biofilm activity. Understanding the interaction at molecular level will lead to sustainably use for anti-biofilm producing marine actinomycetes in pharmaceutical and medicinal applications in the future.
Project description:Actinobacteria are a rich source of bioactive molecules, and genome sequencing has shown that the vast majority of their biosynthetic potential has yet to be explored. However, many of their biosynthetic gene clusters (BGCs) are poorly expressed in the laboratory, which prevents discovery of their cognate natural products. To exploit their full biosynthetic potential, better understanding of the signals that promote the expression of BGCs is needed. Here, we show that the human stress hormone epinephrine (adrenaline) elicits antibiotic production by Actinobacteria. Catechol was established as the likely eliciting moiety, since similar responses were seen for catechol and for the catechol-containing molecules dopamine and catechin but not for related molecules. Exploration of the catechol-responsive strain Streptomyces sp. MBT84 using mass spectral networking revealed elicitation of a BGC that produces the angucycline glycosides aquayamycin, urdamycinone B and galtamycin C. Heterologous expression of the catechol-cleaving enzymes catechol 1,2-dioxygenase or catechol 2,3 dioxygenase counteracted the eliciting effect of catechol. Thus, for the first time we show the activation of natural product biosynthesis by a human hormone, leading to the identification of the ubiquitous catechol moiety as elicitor of BGCs for siderophores and antibiotics.
Project description:Actinobacteria are a rich source of bioactive molecules, and genome sequencing has shown that the vast majority of their biosynthetic potential has yet to be explored. However, many of their biosynthetic gene clusters (BGCs) are poorly expressed in the laboratory, which prevents discovery of their cognate natural products. To exploit their full biosynthetic potential, better understanding of the signals that promote the expression of BGCs is needed. Here, we show that the human stress hormone epinephrine (adrenaline) elicits antibiotic production by Actinobacteria. Catechol was established as the likely eliciting moiety, since similar responses were seen for catechol and for the catechol-containing molecules dopamine and catechin but not for related molecules. Exploration of the catechol-responsive strain Streptomyces sp. MBT84 using mass spectral networking revealed elicitation of a BGC that produces the angucycline glycosides aquayamycin, urdamycinone B and galtamycin C. Heterologous expression of the catechol-cleaving enzymes catechol 1,2-dioxygenase or catechol 2,3 dioxygenase counteracted the eliciting effect of catechol. Thus, for the first time we show the activation of natural product biosynthesis by a human hormone, leading to the identification of the ubiquitous catechol moiety as elicitor of BGCs for siderophores and antibiotics.
Project description:This study is aimed to isolate marine actinomycetes from sediments from Andaman and the Gulf of Thailand. All 101 marine actinomycetes were screened for anti-biofilm activity. Streptomyces sp. GKU 257-1 showed significantly inhibited biofilm formation of E. coli. The evaluation of supernatants of anti-biofilm activity produced by Streptomyces sp. GKU 257-1 has been performed. Since the interaction between marine actinomycetes and biofilm forming bacteria has never been investigated, proteomic analysis has been used to identify whole cell proteins involved in anti–biofilm activity. Understanding the interaction at molecular level will lead to sustainably use for anti-biofilm producing marine actinomycetes in pharmaceutical and medicinal applications in the future.
Project description:Frequently observed in tropical and sub-tropical regions, crops contamination by aflatoxin B1 (AFB1) produced by Aspergillus flavus, is emerging in Europe, due to climate change. Many alternative methods are currently developed to reduce the use of chemical inputs to prevent mycotoxin contamination, such as biocontrol agents (BCAs). Actinobacteria are known to produce many bioactive compounds and some of them are able to reduce in vitro AFB1 concentration. In this context, the present study aims to analyze the effect of a cell free supernatant (CFS) from Streptomyces roseolus liquid culture on A. flavus development, as well as on its transcriptome profile using microarray assay and its impact on AFB1 concentration. To study the impact of Streptomyces roseolus cell free supernatant on global transcriptome of Aspergillus flavus we have employed whole genome microarray expression profiling.