ABSTRACT
Organophosphonates are molecules that contain a very chemically stable carbon-phosphorus (C-P) bond. Microorganisms can utilize phosphonates as potential source of crucial elements for their growth, as developed several pathways to metabolize these compounds. One among these pathways is catalyzed by C-P lyase complex, which has a broad substrate specifity; therefore, it has a wide application in degradation of herbicides deposited in the environment, such as glyphosate. This multi-enzyme system accurately recognized in Escherichia coli and genetic studies have demonstrated that it is encoded by phn operon containing 14 genes (phnC-phnP). The phn operon is a member of the Pho regulon induced by phosphate starvation. Ability to degradation of phosphonates is also found in other microorganisms, especially soil and marine bacteria, that have homologous genes to those in E. coli. Despite the existence of differences in structure and composition of phn gene cluster, each of these strains contains phnGHIJKLM genes necessary in the C-P bond cleavage mechanism. The review provides a detailed description and summary of achievements on the C-P lyase enzymatic pathway over the last 50 years.
Subject(s)
Gram-Negative Bacteria/enzymology , Gram-Positive Bacteria/enzymology , Lyases/chemistry , Binding Sites , Catalysis , Crystallography, X-Ray , Escherichia coli/enzymology , Escherichia coli/genetics , Genes, Bacterial , Glycine/analogs & derivatives , Glycine/chemistry , Gram-Negative Bacteria/genetics , Gram-Positive Bacteria/genetics , Herbicides/chemistry , Inorganic Chemicals/chemistry , Ions , Metals/chemistry , Molecular Conformation , Multigene Family , Operon , Organophosphonates/chemistry , Oxidation-Reduction , Phosphates/chemistry , Phosphorous Acids/chemistry , Soil Microbiology , Substrate Specificity , GlyphosateABSTRACT
Solicoccozyma terricola M 3.1.4., the yeast strain isolated from soil sample from blueberry cultivation in Miedzyrzec Podlaski in Poland, is capable to split of phosphorus to nitrogen and nitrogen to carbon bonds in N-phosphonomethylglycine (PMG, glyphosate). The biodegradation process proceeds in the phosphate-independent manner. It is the first example of a psychrotolerant yeast strain able to degrade PMG via CN bond cleavage accompanied by AMPA formation and not like in most microorganisms via CP bond disruption followed by the sarcosine pathway. Glyphosate oxidoreductase (GOX) type activity was detected in cell-free extracts prepared from S. terricola M 3.1.4. pregrown on 4â¯mM PMG as a sole phosphorus and nitrogen source in cultivation medium.
