(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Bacteria: NE > Terrabacteria group: NE > Actinobacteria [phylum]: NE > Actinobacteria [class]: NE > Streptomycetales: NE > Streptomycetaceae: NE > Streptomyces: NE > Streptomyces scabiei: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MRIRLYLAAIPLVGGAGLAAVATPTATAAACTDIDVVSARGTFEPGTLGF IVGDPVYAALQKKVAGKSLSSYKVNYPADLSPTSAAQGNADLVNHVRSQA ASCPNQRFVLVGYSQGANVVDNSIGISSAGAVVGSPIVATLPAALEPRVS AVLLFGNPIRAIGKSVTGTYQSRTIDFCAAGDPVCENGGGDVGAHLGYRA NADAAAAFAATKI
References
1 moreTitle: Phylogenetic analysis and in-depth characterization of functionally and structurally diverse CE5 cutinases Novy V, Carneiro LV, Shin JH, Larsbrink J, Olsson L Ref: Journal of Biological Chemistry, :101302, 2021 : PubMed
Cutinases are esterases that release fatty acids from the apoplastic layer in plants. As they accept bulky and hydrophobic substrates, cutinases could be used in many applications, ranging from valorization of bark-rich side streams to plastic recycling. Advancement of these applications with cutinases as biocatalysts, however, requires deeper knowledge of the enzymes' biodiversity and structure-function relationships. Here, we mined over 3000 members from Carbohydrate Esterase family 5 (CE5) for putative cutinases and condensed it to 151 genes from known or putative lignocellulose-targeting organisms. The 151 genes were subjected to a phylogenetic analysis. While cutinases with available crystal structures were phylogenetically closely related, we selected nine phylogenic diverse cutinases for characterization. The nine selected cutinases were recombinantly produced and their kinetic activity was characterized against para-nitrophenol substrates esterified with consecutively longer alkyl chains (pNP-C(2) to C(16)). The investigated cutinases each had a unique activity fingerprint against tested pNP-substrates. The five enzymes with the highest activity on pNP-C(12) and C(16), indicative of activity on bulky hydrophobic compounds, were selected for in-depth kinetic and structure-function analysis. All five enzymes showed a decrease in k(cat) values with increasing substrate chain length, while K(M) values and binding energies (calculated from in silico docking analysis) improved. Two cutinases from Fusarium solani and Cryptococcus sp. exhibited outstandingly low K(M) values, resulting in high catalytic efficiencies towards pNP-C(16). Docking analysis suggested that different clades of the phylogenetic tree may harbor enzymes with different modes of substrate interaction, involving a solvent-exposed catalytic triad, a lipase-like lid, or a clamshell-like active site possibly formed by flexible loops.
The genome of Streptomyces scabies, the predominant causal agent of potato common scab, encodes a potential cutinase, the protein Sub1, which was previously shown to be specifically induced in the presence of suberin. The sub1 gene was expressed in Escherichia coli and the recombinant protein Sub1 was purified and characterized. The enzyme was shown to be versatile because it hydrolyzes a number of natural and synthetic substrates. Sub1 hydrolyzed p-nitrophenyl esters, with the hydrolysis of those harboring short carbon chains being the most effective. The Vmax and Km values of Sub1 for p-nitrophenyl butyrate were 2.36 mol g(-1) min(-1) and 5.7 10(-4) M, respectively. Sub1 hydrolyzed the recalcitrant polymers cutin and suberin because the release of fatty acids from these substrates was observed following the incubation of the enzyme with these polymers. Furthermore, the hydrolyzing activity of the esterase Sub1 on the synthetic polymer polyethylene terephthalate (PET) was demonstrated by the release of terephthalic acid (TA). Sub1 activity on PET was markedly enhanced by the addition of Triton and was shown to be stable at 37 degrees C for at least 20 d.
Plant-pathogenic Streptomyces spp. cause scab disease on economically important root and tuber crops, the most important of which is potato. Key virulence determinants produced by these species include the cellulose synthesis inhibitor, thaxtomin A, and the secreted Nec1 protein that is required for colonization of the plant host. Recently, the genome sequence of Streptomyces scabies 87-22 was completed, and a biosynthetic cluster was identified that is predicted to synthesize a novel compound similar to coronafacic acid (CFA), a component of the virulence-associated coronatine phytotoxin produced by the plant-pathogenic bacterium Pseudomonas syringae. Southern analysis indicated that the cfa-like cluster in S. scabies 87-22 is likely conserved in other strains of S. scabies but is absent from two other pathogenic streptomycetes, S. turgidiscabies and S. acidiscabies. Transcriptional analyses demonstrated that the cluster is expressed during plant-microbe interactions and that expression requires a transcriptional regulator embedded in the cluster as well as the bldA tRNA. A knockout strain of the biosynthetic cluster displayed a reduced virulence phenotype on tobacco seedlings compared with the wild-type strain. Thus, the cfa-like biosynthetic cluster is a newly discovered locus in S. scabies that contributes to host-pathogen interactions.
        
1 lessTitle: Perspectives on the Role of Enzymatic Biocatalysis for the Degradation of Plastic PET Magalhaes RP, Cunha JM, Sousa SF Ref: Int J Mol Sci, 22:11257, 2021 : PubMed
Plastics are highly durable and widely used materials. Current methodologies of plastic degradation, elimination, and recycling are flawed. In recent years, biodegradation (the usage of microorganisms for material recycling) has grown as a valid alternative to previously used methods. The evolution of bioengineering techniques and the discovery of novel microorganisms and enzymes with degradation ability have been key. One of the most produced plastics is PET, a long chain polymer of terephthalic acid (TPA) and ethylene glycol (EG) repeating monomers. Many enzymes with PET degradation activity have been discovered, characterized, and engineered in the last few years. However, classification and integrated knowledge of these enzymes are not trivial. Therefore, in this work we present a summary of currently known PET degrading enzymes, focusing on their structural and activity characteristics, and summarizing engineering efforts to improve activity. Although several high potential enzymes have been discovered, further efforts to improve activity and thermal stability are necessary.
        
Title: Phylogenetic analysis and in-depth characterization of functionally and structurally diverse CE5 cutinases Novy V, Carneiro LV, Shin JH, Larsbrink J, Olsson L Ref: Journal of Biological Chemistry, :101302, 2021 : PubMed
Cutinases are esterases that release fatty acids from the apoplastic layer in plants. As they accept bulky and hydrophobic substrates, cutinases could be used in many applications, ranging from valorization of bark-rich side streams to plastic recycling. Advancement of these applications with cutinases as biocatalysts, however, requires deeper knowledge of the enzymes' biodiversity and structure-function relationships. Here, we mined over 3000 members from Carbohydrate Esterase family 5 (CE5) for putative cutinases and condensed it to 151 genes from known or putative lignocellulose-targeting organisms. The 151 genes were subjected to a phylogenetic analysis. While cutinases with available crystal structures were phylogenetically closely related, we selected nine phylogenic diverse cutinases for characterization. The nine selected cutinases were recombinantly produced and their kinetic activity was characterized against para-nitrophenol substrates esterified with consecutively longer alkyl chains (pNP-C(2) to C(16)). The investigated cutinases each had a unique activity fingerprint against tested pNP-substrates. The five enzymes with the highest activity on pNP-C(12) and C(16), indicative of activity on bulky hydrophobic compounds, were selected for in-depth kinetic and structure-function analysis. All five enzymes showed a decrease in k(cat) values with increasing substrate chain length, while K(M) values and binding energies (calculated from in silico docking analysis) improved. Two cutinases from Fusarium solani and Cryptococcus sp. exhibited outstandingly low K(M) values, resulting in high catalytic efficiencies towards pNP-C(16). Docking analysis suggested that different clades of the phylogenetic tree may harbor enzymes with different modes of substrate interaction, involving a solvent-exposed catalytic triad, a lipase-like lid, or a clamshell-like active site possibly formed by flexible loops.
The genome of Streptomyces scabies, the predominant causal agent of potato common scab, encodes a potential cutinase, the protein Sub1, which was previously shown to be specifically induced in the presence of suberin. The sub1 gene was expressed in Escherichia coli and the recombinant protein Sub1 was purified and characterized. The enzyme was shown to be versatile because it hydrolyzes a number of natural and synthetic substrates. Sub1 hydrolyzed p-nitrophenyl esters, with the hydrolysis of those harboring short carbon chains being the most effective. The Vmax and Km values of Sub1 for p-nitrophenyl butyrate were 2.36 mol g(-1) min(-1) and 5.7 10(-4) M, respectively. Sub1 hydrolyzed the recalcitrant polymers cutin and suberin because the release of fatty acids from these substrates was observed following the incubation of the enzyme with these polymers. Furthermore, the hydrolyzing activity of the esterase Sub1 on the synthetic polymer polyethylene terephthalate (PET) was demonstrated by the release of terephthalic acid (TA). Sub1 activity on PET was markedly enhanced by the addition of Triton and was shown to be stable at 37 degrees C for at least 20 d.
Plant-pathogenic Streptomyces spp. cause scab disease on economically important root and tuber crops, the most important of which is potato. Key virulence determinants produced by these species include the cellulose synthesis inhibitor, thaxtomin A, and the secreted Nec1 protein that is required for colonization of the plant host. Recently, the genome sequence of Streptomyces scabies 87-22 was completed, and a biosynthetic cluster was identified that is predicted to synthesize a novel compound similar to coronafacic acid (CFA), a component of the virulence-associated coronatine phytotoxin produced by the plant-pathogenic bacterium Pseudomonas syringae. Southern analysis indicated that the cfa-like cluster in S. scabies 87-22 is likely conserved in other strains of S. scabies but is absent from two other pathogenic streptomycetes, S. turgidiscabies and S. acidiscabies. Transcriptional analyses demonstrated that the cluster is expressed during plant-microbe interactions and that expression requires a transcriptional regulator embedded in the cluster as well as the bldA tRNA. A knockout strain of the biosynthetic cluster displayed a reduced virulence phenotype on tobacco seedlings compared with the wild-type strain. Thus, the cfa-like biosynthetic cluster is a newly discovered locus in S. scabies that contributes to host-pathogen interactions.