biodegradation
Enzymology and Protein EngineeringHexachlorobenzene Monooxygenase Substrate Selectivity and Catalysis: Structural and Biochemical InsightsAs an endocrine disrupter and possible carcinogen to human beings, hexachlorobenzene (HCB) is especially resistant to biodegradation, largely due to difficulty in its dechlorination. The lack of knowledge of HCB dechlorinases limits their application in bioremediation. Recently, an HCB monooxygenase, HcbA1A3, representing the only naturally occurring aerobic HCB dechlorinase known so far, was reported. Here, we report its biochemical...
BiodegradationCarbamate C-N Hydrolase Gene ameH Responsible for the Detoxification Step of Methomyl Degradation in Aminobacter aminovorans Strain MDW-2Based on the structural characteristic, carbamate insecticides can be classified into oxime carbamates (methomyl, aldicarb, oxamyl, etc.) and N-methyl carbamates (carbaryl, carbofuran, isoprocarb, etc.). So far, research on the degradation of carbamate pesticides has mainly focused on the detoxification step and hydrolysis of their carbamate bond. Several genes, such as cehA, mcbA, cahA, and mcd...
Environmental MicrobiologyThe Interactive Effects of Crude Oil and Corexit 9500 on Their Biodegradation in Arctic SeawaterChemical dispersants such as Corexit 9500 are commonly used in oil spill response and are currently under consideration for use in the Arctic, where their fate and effects have not been well studied. This research was performed to determine the interactive effects of the copresence of crude oil and Corexit 9500 on the degradation of components from each mixture and the associated microbial community structure over time in Arctic...
BiodegradationFast and Facile Biodegradation of Polystyrene by the Gut Microbial Flora of Plesiophthalmus davidis LarvaePS is widely produced in the modern world, but it is robust against biodegradation. A few studies reported the biodegradation of PS, but most of them merely observed its weight loss; fewer were able to find its chemical modifications, which are rather direct evidence of biodegradation, by using limited organisms. Therefore, it is required to find an effective way to decompose PS using various kinds of organisms. Herein, we discovered a...
Biodegradation | SpotlightMicrobial Degradation of Pyridine: a Complete Pathway in Arthrobacter sp. Strain 68b DecipheredThe biodegradation pathway of pyridine, a notorious toxicant, is relatively unexplored, as no genetic data related to this process have ever been presented. In this paper, we describe the plasmid-borne pyr gene cluster, which includes the complete set of genes responsible for the degradation of pyridine. A key enzyme, the monooxygenase PyrA, which is responsible for the first step of the catabolic pathway, performs an oxidative...
Biodegradation | SpotlightAn Aerobic Hybrid Phthalate Degradation Pathway via Phthaloyl-Coenzyme A in Denitrifying BacteriaPhthalic acid esters (PAEs) are industrially produced on a million-ton scale per year and are predominantly used as plasticizers. They are classified as environmentally relevant xenobiotics with a number of adverse health effects, including endocrine-disrupting activity. Biodegradation by microorganisms is considered the most effective process to eliminate PAEs from the environment. It is usually initiated by the hydrolysis of PAEs to...
Enzymology and Protein EngineeringAn α/β-Hydrolase Fold Subfamily Comprising Pseudomonas Quinolone Signal-Cleaving DioxygenasesFunctional annotation of protein sequences is a major requirement for the investigation of metabolic pathways and the identification of sought-after biocatalysts. To identify heterocyclic ring-cleaving dioxygenases within the huge superfamily of α/β-hydrolase fold proteins, we defined search and validation criteria for the primarily motif-based identification of 3-hydroxy-4(1H)-quinolone 2,4-dioxygenases (HQD). HQDs are key...
BiodegradationAnaerobic Degradation of Syringic Acid by an Adapted Strain of Rhodopseudomonas palustrisLignin is the most abundant aromatic polymer on Earth and a resource that could eventually substitute for fossil fuels as a source of aromatic compounds for industrial and biotechnological applications. Engineering microorganisms for the production of aromatic-based biochemicals requires detailed knowledge of the metabolic pathways for the degradation of aromatics that are present in lignin. Our isolation and analysis of a...
Biodegradation | SpotlightCyanuric Acid Biodegradation via Biuret: Physiology, Taxonomy, and Geospatial DistributionCyanuric acid is produced naturally as a contaminant in urea fertilizer, and it is used as a chlorine stabilizer in swimming pools. Cyanuric acid-degrading bacteria are used commercially in removing cyanuric acid from pool water when it exceeds desired levels. The total volume of cyanuric acid produced annually exceeds 200 million kilograms, most of which enters the natural environment. In this context, it is important to have a global...
BiodegradationMethanogenic Degradation of Long n-Alkanes Requires Fumarate-Dependent ActivationMethanogenic hydrocarbon degradation is the major process for oil degradation in subsurface oil reservoirs and is blamed for the formation of heavy oil and oil sands. Addition of n-alkanes to fumarate yielding alkyl-substituted succinates is a well-characterized anaerobic activation mechanism for hydrocarbons and is the most common activation mechanism in the anaerobic biodegradation of n-alkanes with chain lengths...