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Curcumin (CUR) has been shown to possess significant anti-inflammatory properties and significant wound healing potential. Additionally, lignin (LIG) is a renewable biomacromolecule with well-known antioxidant and antimicrobial properties, which makes this biomacromolecule a good candidate to be included in medical materials, such as wound dressings. Although many of the wound dressings used at present have interesting features, some are limited in terms of antibacterial properties. To address these limitations, in the present work, both CUR and LIG were combined with poly(caprolactone) (PCL), a biocompatible polymer, to obtain dressings with antioxidant and antimicrobial properties for wound healing treatment. Moreover, D-Panthenol (DPA) was included in the composite materials formulation due to its skin regenerative ability by enhancing epidermal differentiation. Semi-solid extrusion (SSE) 3D printing was used to manufacture wound dressings without the use of any solvents. 3D-printed dressings provided a sustained DPA and CUR release for periods of up to 4 and 35 days, respectively. A DPPH (2,2-diphenyl-1-picrylhydrozyl) assay was performed confirming that the presence of LIG and CUR provided antioxidant properties to the 3D-printed dressings. Additionally, these 3D-printed materials showed a marked resistance to adherence of Staphylococcus aureus when compared to the PCL control 3D-printed samples, resulting in substantial reductions of up to 89.9% and 98.9% after incubation periods of 4 h and 24 h respectively. Although, all of the 3D-printed materials were able to provide a supportive environment for cellular attachment, viability and growth, the combination of both bioactive compounds CUR and DPA exhibited the most significant values for cell viability and proliferation. In vivo wound healing study performed in Wistar rats showed that dressings containing these novel two compounds CUR and DPA exhibited marked improvement at any stage of the treatment process.

The life of bacteria is challenging, to endure bacteria employ a range of mechanisms to optimize their environment, including deploying the type VI secretion system (T6SS). Acting as a bacterial crossbow, this system delivers effectors responsible for subverting host cells, killing competitors and facilitating general secretion to access common goods. Due to its importance, this lethal machine has been evolutionarily maintained, disseminated and specialized to fulfil these vital functions. In fact, T6SS structural clusters are present in over 25% of Gram-negative bacteria, varying in number from one to six different genetic clusters per organism. Since its discovery in 2006, research on the T6SS has rapidly progressed, yielding remarkable breakthroughs. The identification and characterization of novel components of the T6SS, combined with biochemical and structural studies, have revealed fascinating mechanisms governing its assembly, loading, firing and disassembly processes. Recent findings have also demonstrated the efficacy of this system against fungal and Gram-positive cells, expanding its scope. Ongoing research continues to uncover an extensive and expanding repertoire of T6SS effectors, the genuine mediators of T6SS function. These studies are shedding light on new aspects of the biology of prokaryotic and eukaryotic organisms. This review provides a comprehensive overview of the T6SS, highlighting recent discoveries of its structure and the diversity of its effectors. Additionally, it injects a personal perspective on avenues for future research, aiming to deepen our understanding of this combative system.

Curcumin (CUR) has been shown to possess significant anti-inflammatory properties and significant wound healing potential. Additionally, lignin (LIG) is a renewable biomacromolecule with well-known antioxidant and antimicrobial properties, which makes this biomacromolecule a good candidate to be included in medical materials, such as wound dressings. Although many of the wound dressings used at present have interesting features, some are limited in terms of antibacterial properties. To address these limitations, in the present work, both CUR and LIG were combined with poly(caprolactone) (PCL), a biocompatible polymer, to obtain dressings with antioxidant and antimicrobial properties for wound healing treatment. Moreover, D-Panthenol (DPA) was included in the composite materials formulation due to its skin regenerative ability by enhancing epidermal differentiation. Semi-solid extrusion (SSE) 3D printing was used to manufacture wound dressings without the use of any solvents. 3D-printed dressings provided a sustained DPA and CUR release for periods of up to 4 and 35 days, respectively. A DPPH (2,2-diphenyl-1-picrylhydrozyl) assay was performed confirming that the presence of LIG and CUR provided antioxidant properties to the 3D-printed dressings. Additionally, these 3D-printed materials showed a marked resistance to adherence of Staphylococcus aureus when compared to the PCL control 3D-printed samples, resulting in substantial reductions of up to 89.9% and 98.9% after incubation periods of 4 h and 24 h respectively. Although, all of the 3D-printed materials were able to provide a supportive environment for cellular attachment, viability and growth, the combination of both bioactive compounds CUR and DPA exhibited the most significant values for cell viability and proliferation. In vivo wound healing study performed in Wistar rats showed that dressings containing these novel two compounds CUR and DPA exhibited marked improvement at any stage of the treatment process.

The life of bacteria is challenging, to endure bacteria employ a range of mechanisms to optimize their environment, including deploying the type VI secretion system (T6SS). Acting as a bacterial crossbow, this system delivers effectors responsible for subverting host cells, killing competitors and facilitating general secretion to access common goods. Due to its importance, this lethal machine has been evolutionarily maintained, disseminated and specialized to fulfil these vital functions. In fact, T6SS structural clusters are present in over 25% of Gram-negative bacteria, varying in number from one to six different genetic clusters per organism. Since its discovery in 2006, research on the T6SS has rapidly progressed, yielding remarkable breakthroughs. The identification and characterization of novel components of the T6SS, combined with biochemical and structural studies, have revealed fascinating mechanisms governing its assembly, loading, firing and disassembly processes. Recent findings have also demonstrated the efficacy of this system against fungal and Gram-positive cells, expanding its scope. Ongoing research continues to uncover an extensive and expanding repertoire of T6SS effectors, the genuine mediators of T6SS function. These studies are shedding light on new aspects of the biology of prokaryotic and eukaryotic organisms. This review provides a comprehensive overview of the T6SS, highlighting recent discoveries of its structure and the diversity of its effectors. Additionally, it injects a personal perspective on avenues for future research, aiming to deepen our understanding of this combative system.

Curcumin (CUR) has been shown to possess significant anti-inflammatory properties and significant wound healing potential. Additionally, lignin (LIG) is a renewable biomacromolecule with well-known antioxidant and antimicrobial properties, which makes this biomacromolecule a good candidate to be included in medical materials, such as wound dressings. Although many of the wound dressings used at present have interesting features, some are limited in terms of antibacterial properties. To address these limitations, in the present work, both CUR and LIG were combined with poly(caprolactone) (PCL), a biocompatible polymer, to obtain dressings with antioxidant and antimicrobial properties for wound healing treatment. Moreover, D-Panthenol (DPA) was included in the composite materials formulation due to its skin regenerative ability by enhancing epidermal differentiation. Semi-solid extrusion (SSE) 3D printing was used to manufacture wound dressings without the use of any solvents. 3D-printed dressings provided a sustained DPA and CUR release for periods of up to 4 and 35 days, respectively. A DPPH (2,2-diphenyl-1-picrylhydrozyl) assay was performed confirming that the presence of LIG and CUR provided antioxidant properties to the 3D-printed dressings. Additionally, these 3D-printed materials showed a marked resistance to adherence of Staphylococcus aureus when compared to the PCL control 3D-printed samples, resulting in substantial reductions of up to 89.9% and 98.9% after incubation periods of 4 h and 24 h respectively. Although, all of the 3D-printed materials were able to provide a supportive environment for cellular attachment, viability and growth, the combination of both bioactive compounds CUR and DPA exhibited the most significant values for cell viability and proliferation. In vivo wound healing study performed in Wistar rats showed that dressings containing these novel two compounds CUR and DPA exhibited marked improvement at any stage of the treatment process.

As time passes, mutations accumulate in the genomes of all living organisms. These changes promote genetic diversity, but also precipitate ageing and the initiation of cancer. Food is a common source of mutagens, but little is known about how nutritional factors cause lasting genetic changes in the consuming organism. Here, we describe an unusual genetic interaction between DNA repair in the unicellular amoeba Dictyostelium discoideum and its natural bacterial food source. We found that Dictyostelium deficient in the DNA repair nuclease Xpf (xpf−) display a severe and specific growth defect when feeding on bacteria. Despite being proficient in the phagocytosis and digestion of bacteria, over time, xpf− Dictyostelium feeding on bacteria cease to grow and in many instances die. The Xpf nuclease activity is required for sustained growth using a bacterial food source. Furthermore, the ingestion of this food source leads to a striking accumulation of mutations in the genome of xpf− Dictyostelium. This work therefore establishes Dictyostelium as a model genetic system to dissect nutritional genotoxicity, providing insight into how phagocytosis can induce mutagenesis and compromise survival fitness.

As time passes, mutations accumulate in the genomes of all living organisms. These changes promote genetic diversity, but also precipitate ageing and the initiation of cancer. Food is a common source of mutagens, but little is known about how nutritional factors cause lasting genetic changes in the consuming organism. Here, we describe an unusual genetic interaction between DNA repair in the unicellular amoeba Dictyostelium discoideum and its natural bacterial food source. We found that Dictyostelium deficient in the DNA repair nuclease Xpf (xpf−) display a severe and specific growth defect when feeding on bacteria. Despite being proficient in the phagocytosis and digestion of bacteria, over time, xpf− Dictyostelium feeding on bacteria cease to grow and in many instances die. The Xpf nuclease activity is required for sustained growth using a bacterial food source. Furthermore, the ingestion of this food source leads to a striking accumulation of mutations in the genome of xpf− Dictyostelium. This work therefore establishes Dictyostelium as a model genetic system to dissect nutritional genotoxicity, providing insight into how phagocytosis can induce mutagenesis and compromise survival fitness.

As time passes, mutations accumulate in the genomes of all living organisms. These changes promote genetic diversity, but also precipitate ageing and the initiation of cancer. Food is a common source of mutagens, but little is known about how nutritional factors cause lasting genetic changes in the consuming organism. Here, we describe an unusual genetic interaction between DNA repair in the unicellular amoeba Dictyostelium discoideum and its natural bacterial food source. We found that Dictyostelium deficient in the DNA repair nuclease Xpf (xpf−) display a severe and specific growth defect when feeding on bacteria. Despite being proficient in the phagocytosis and digestion of bacteria, over time, xpf− Dictyostelium feeding on bacteria cease to grow and in many instances die. The Xpf nuclease activity is required for sustained growth using a bacterial food source. Furthermore, the ingestion of this food source leads to a striking accumulation of mutations in the genome of xpf− Dictyostelium. This work therefore establishes Dictyostelium as a model genetic system to dissect nutritional genotoxicity, providing insight into how phagocytosis can induce mutagenesis and compromise survival fitness.

As time passes, mutations accumulate in the genomes of all living organisms. These changes promote genetic diversity, but also precipitate ageing and the initiation of cancer. Food is a common source of mutagens, but little is known about how nutritional factors cause lasting genetic changes in the consuming organism. Here, we describe an unusual genetic interaction between DNA repair in the unicellular amoeba Dictyostelium discoideum and its natural bacterial food source. We found that Dictyostelium deficient in the DNA repair nuclease Xpf (xpf−) display a severe and specific growth defect when feeding on bacteria. Despite being proficient in the phagocytosis and digestion of bacteria, over time, xpf− Dictyostelium feeding on bacteria cease to grow and in many instances die. The Xpf nuclease activity is required for sustained growth using a bacterial food source. Furthermore, the ingestion of this food source leads to a striking accumulation of mutations in the genome of xpf− Dictyostelium. This work therefore establishes Dictyostelium as a model genetic system to dissect nutritional genotoxicity, providing insight into how phagocytosis can induce mutagenesis and compromise survival fitness.

Endogenous formaldehyde is produced by numerous biochemical pathways fundamental to life, and it can crosslink both DNA and proteins. However, the consequences of its accumulation are unclear. Here we show that endogenous formaldehyde is removed by the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR), and Adh5−/− mice therefore accumulate formaldehyde adducts in DNA. The repair of this damage is mediated by FANCD2, a DNA crosslink repair protein. Adh5−/−Fancd2−/− mice reveal an essential requirement for these protection mechanisms in hematopoietic stem cells (HSCs), leading to their depletion and precipitating bone marrow failure. More widespread formaldehyde-induced DNA damage also causes karyomegaly and dysfunction of hepatocytes and nephrons. Bone marrow transplantation not only rescued hematopoiesis but, surprisingly, also preserved nephron function. Nevertheless, all of these animals eventually developed fatal malignancies. Formaldehyde is therefore an important source of endogenous DNA damage that is counteracted in mammals by a conserved protection mechanism.

Endogenous formaldehyde is produced by numerous biochemical pathways fundamental to life, and it can crosslink both DNA and proteins. However, the consequences of its accumulation are unclear. Here we show that endogenous formaldehyde is removed by the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR), and Adh5−/− mice therefore accumulate formaldehyde adducts in DNA. The repair of this damage is mediated by FANCD2, a DNA crosslink repair protein. Adh5−/−Fancd2−/− mice reveal an essential requirement for these protection mechanisms in hematopoietic stem cells (HSCs), leading to their depletion and precipitating bone marrow failure. More widespread formaldehyde-induced DNA damage also causes karyomegaly and dysfunction of hepatocytes and nephrons. Bone marrow transplantation not only rescued hematopoiesis but, surprisingly, also preserved nephron function. Nevertheless, all of these animals eventually developed fatal malignancies. Formaldehyde is therefore an important source of endogenous DNA damage that is counteracted in mammals by a conserved protection mechanism.

Endogenous formaldehyde is produced by numerous biochemical pathways fundamental to life, and it can crosslink both DNA and proteins. However, the consequences of its accumulation are unclear. Here we show that endogenous formaldehyde is removed by the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR), and Adh5−/− mice therefore accumulate formaldehyde adducts in DNA. The repair of this damage is mediated by FANCD2, a DNA crosslink repair protein. Adh5−/−Fancd2−/− mice reveal an essential requirement for these protection mechanisms in hematopoietic stem cells (HSCs), leading to their depletion and precipitating bone marrow failure. More widespread formaldehyde-induced DNA damage also causes karyomegaly and dysfunction of hepatocytes and nephrons. Bone marrow transplantation not only rescued hematopoiesis but, surprisingly, also preserved nephron function. Nevertheless, all of these animals eventually developed fatal malignancies. Formaldehyde is therefore an important source of endogenous DNA damage that is counteracted in mammals by a conserved protection mechanism.

Endogenous formaldehyde is produced by numerous biochemical pathways fundamental to life, and it can crosslink both DNA and proteins. However, the consequences of its accumulation are unclear. Here we show that endogenous formaldehyde is removed by the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR), and Adh5−/− mice therefore accumulate formaldehyde adducts in DNA. The repair of this damage is mediated by FANCD2, a DNA crosslink repair protein. Adh5−/−Fancd2−/− mice reveal an essential requirement for these protection mechanisms in hematopoietic stem cells (HSCs), leading to their depletion and precipitating bone marrow failure. More widespread formaldehyde-induced DNA damage also causes karyomegaly and dysfunction of hepatocytes and nephrons. Bone marrow transplantation not only rescued hematopoiesis but, surprisingly, also preserved nephron function. Nevertheless, all of these animals eventually developed fatal malignancies. Formaldehyde is therefore an important source of endogenous DNA damage that is counteracted in mammals by a conserved protection mechanism.