165 results about "Monooxygenase" patented technology

According to the invention, the monooxygenase CYP102A1 from Bacillus megaterium is subjected to system modification and optimization, a series of monooxygenase mutants with improved activity and improved debenzylation selectivity are obtained, the activity of the mutant with the optimal effect is improved by 93.4 times compared with that of wild type monooxygenase CYP102A1, and the selectivity is improved to 99.5% from 33.2%. The monooxygenase mutant can be applied to catalytic synthesis of 3R, 5S-dihydroxy compounds, synthesis steps are simplified, reaction selectivity is improved, reaction conditions are mild, the monooxygenase mutant is environmentally friendly and efficient, and the overall efficiency of statin drug synthesis can be improved.

The invention discloses a Vinck Cellulomicrobe and application thereof in degradation of corn straw and improvement of soil fertility, and belongs to the field of agricultural microbial technology and solid waste resource utilization. The bacterial strain can secrete a plurality of hydrolase and oxidase including AA10 family lytic polysaccharide monooxygenase, AA2 peroxidase, GH3 and GH1 beta-glucosidase, GH16 / GH17 beta-glucosan endonuclease and AA1 multi-copper oxidase. The bacterial strain has the advantages that the bacterial strain can secrete a plurality of hydrolase and oxidase; fermentation liquor is applied to soil according to the straw mass ratio of 1: 5, and the corn straw degradation rate can be increased under the condition that the mass ratio of soil to straw is 100: 1. Meanwhile, the microbial agent can synergistically improve soil nutrients and increase the contents of rapidly available phosphorus, rapidly available potassium, alkali-hydrolyzable nitrogen, soluble organic carbon and total phosphorus in soil. According to the microbial agent, a straw lignocellulose structure is effectively cracked through a multi-enzyme system synergistic effect, and the dual effects of accelerating straw degradation and improving soil fertility are achieved.

The invention discloses a recombinant pichia pastoris strain with high yield of retinaldehyde as well as a construction method and application of the recombinant pichia pastoris strain. The recombinant pichia pastoris strain is obtained by expressing dehydrogenase Zwf1, phosphate dehydrogenase Gnd2, NADH kinase Pos5 and two copied beta-carotene-15, 15 '-monooxygenase BCMO in host bacteria. Wherein the host bacterium is a pichia pastoris gene modified strain PP-B (Propene Polymer-B). The retinaldehyde production performance of the recombinant strain is verified based on cofactor engineering and the copy number of key enzymes, and the retinaldehyde production capacity of the pichia pastoris is further improved. The recombinant pichia pastoris disclosed by the invention is simple in construction method, can better promote the synthesis of retinol, and is beneficial to industrial production as the engineering strain can efficiently synthesize retinol by using methanol as a unique carbon source through amplification fermentation in a 5L fermentation tank.

The invention discloses an early diagnosis and early screening kit for joint detection of Parkinson's disease and application of the kit, and relates to the technical field of medical treatment. The kit is used for combined detection of three proteins, namely alpha synuclein (alpha-Syn), tyrosine 3-monooxygenase / tryptophan 5-monooxygenase activated protein zeta (YWHAZ) and myosin light chain 6 (Myl6), immunochromatography, chemiluminescence and other methods and a double-antibody sandwich method are adopted, the diagnosis efficiency of the YWHAZ protein is prominent, the AUC reaches 0.96, and the detection sensitivity is high. The AUC of Myl6 is 0.92, the AUC of alpha-Syn is 0.82, the joint detection AUC is up to 0.98, the kit is newly added with a time-resolved fluorescence immunochromatography technology, low-background and high-sensitivity detection is realized through a lanthanide-labeled antibody, the change of related protein expression level can be detected in the early stage of Parkinson's disease, early screening and diagnosis are realized, and the kit has the advantages of high specificity, joint detection up to 95%, high sensitivity, high sensitivity and the like. The joint detection reaches 96%, the operation is simple and convenient, and the sample requirement is low.

The invention discloses a lytic polysaccharide monooxygenase mutant as well as a preparation method and application thereof. In order to solve the problems of low expression level, poor stability and the like of the existing lysing polysaccharide monooxygenase in a microbial expression system, the lysing polysaccharide monooxygenase RsLPMO9 is mutated to obtain a multi-site mutant of which the amino acid sequence is shown as SEQ ID NO.2, and the expression quantity of the multi-site mutant is obviously higher than that of a wild type protein RsLPMO9. The analysis of the thermal stability shows that the thermal stability of the multi-site mutant is obviously improved compared with that of the wild protein RsLPMO9, and the lytic polysaccharide monooxygenase mutant provided by the invention has an application prospect in the aspects of degrading biomass or plant polysaccharide and the like.

The invention discloses an application of an isoeugenol monooxygenase mutant in production of isoeugenol vanillin, which comprises the steps of recombinant strain construction, fermentation culture of recombinant strains and catalytic reaction of fermentation broth, and the isoeugenol monooxygenase mutant is mutated through an isoeugenol monooxygenase amino acid sequence of wild fungi WT. And the thalli are expressed by escherichia coli, so that a series of thalli with a promoting effect on the catalytic efficiency of vanillin production are formed. The mutant super-efficient enzyme catalyst with the catalytic conversion rate reaching up to 98.5% or above is obtained through screening, the defects of low efficiency, pollution, high energy consumption and the like of traditional chemical catalyst production are overcome, and the mutant super-efficient enzyme catalyst is more suitable for green industrial production requirements and worthy of being popularized to industrial use.

The invention discloses an alcohol dehydrogenase mutant for high yield of tea flavor ketone and application of the alcohol dehydrogenase mutant in a one-pot method. The mutant is A182L or A182L / V214T. The alcohol dehydrogenase mutant has high catalytic activity on 4-hydroxyisophorone, and the yield of tea flavor ketone prepared by catalysis of the mutant A182L / V214T can reach 97% and is 3.73 times that of an original enzyme; the alcohol dehydrogenase mutant has high catalytic activity of synthesizing the tea aroma ketone through one-pot catalysis of isophorone, and the yield of the tea aroma ketone obtained through direct oxidation of isophorone by jointly using the mutant A182L / V214T and a cytochrome P450BM3 monooxygenase mutant can reach 92%; the alcohol dehydrogenase mutant has the advantages of simple production process, mild reaction conditions and environment-friendly production process, is beneficial to the industrial production of the tea flavor ketone, and has wide application prospects.

The invention relates to a method for increasing the yield of glucose biologically converted from corn straws, which comprises the following steps of: carrying out composite pretreatment on the corn straws by using NaOH and urea, and then carrying out step-by-step enzymolysis, namely carrying out enzymolysis on the corn straws by using pleurotus eryngii lysate polysaccharide monooxygenase in the first step, and adding cellulase for further enzymolysis to produce the glucose in the second step, the pleuromutilus rubra lysate polysaccharide monooxygenase is a compound enzyme composed of PdLPMO9A and PdLPMO9B according to a ratio of (1: 2)-(1: 4). According to the method disclosed by the invention, the corn straws are subjected to specific pretreatment, the compound enzyme is formed by adopting the pleurotus eryngii lysate polysaccharide monooxygenase PdLPMO9A and PdLPMO9B according to a specific proportion, and the compound enzyme and the cellulase are used for performing enzymolysis on the corn straws step by step, so that the biological conversion efficiency of the corn straws is effectively improved under the same enzymolysis time, and the yield of glucose is improved and reaches 0.642 g / g of straws.

The present application relates to a kind of sulfide monooxygenase mutant and its application in esomeprazole synthesis.The sulfide monooxygenase mutant, its encoding gene, the preparation method of the recombinant expression vector containing the gene sequence, co-expression recombinant vector and recombinant expression transformant, and the application of the recombinant sulfide monooxygenase mutant catalyst in esomeprazole synthesis are specifically disclosed.Compared with other sulfide monooxygenases, the sulfide monooxygenase mutant obtained by the present application can efficiently utilize the coenzyme NADH with lower cost and higher stability to catalyze the asymmetric oxidation reaction of omeprazole sulfide, prepare esomeprazole, has the advantages of high substrate concentration, mild reaction condition, environment-friendly, simple operation, high yield, low production cost and good industrial application prospect.

The invention discloses a method and a device for degrading bisphenol A by using a propane matrix membrane bio-membrane reactor, and belongs to the technical field of microorganism application. The method specifically comprises the following steps: inoculating activated sludge into a membrane bio-membrane reactor with a basic inorganic salt culture medium, and introducing propane to promote the growth of a bio-membrane on hollow fiber membrane filaments in the membrane bio-membrane reactor, so as to obtain the membrane bio-membrane reactor after membrane formation is completed; the method comprises the following steps: introducing bisphenol A-containing wastewater to be treated into a membrane bio-membrane reactor, continuously introducing propane, and inducing microorganisms to express alkane monooxygenase and cytochrome P450 monooxygenase, thereby promoting hydroxylation of bisphenol A and degrading bisphenol A into a downstream product of which the toxicity is lower than that of bisphenol A. The propane is used as a carbon source and an electron donor, the propane can be efficiently utilized to provide a safe and good environment for biodegradation of bisphenol A, and secondary pollution possibly caused by a traditional carbon source is avoided.

The invention discloses a method for directionally preparing indigo blue or indirubin by biocatalytically converting indoleglycoside fermentation liquor, which is characterized in that beta-glucosidase Asbg1 and flavin-dependent monooxygenase MaFMO are combined, and the indoleglycoside fermentation liquor is used as a substrate to directionally prepare the indigo blue or indirubin. A glucose dehydrogenase (GDH)-mediated NADPH circulating system is introduced as a process supply cofactor, and then process conditions are optimized and regulated, so that a process for directionally preparing the indigo blue or indirubin by taking the indole glycoside fermentation liquor as a substrate is established, and the directional preparation of the indigo blue or indirubin is realized. The process provides a method for realizing green and efficient directional preparation of indigo blue or indirubin.

The invention discloses a genetically engineered bacterium and an application of the genetically engineered bacterium in production of farnesene. The genetically engineered bacterium takes saccharomyces cerevisiae as a chassis strain; an exogenous beta-farnesene synthase gene is integrated, an ERG9 gene is knocked out, a promoter of a truncated HMG1 gene is replaced with an ANB1 promoter, an exogenous transhydrogenase gene is integrated and driven by a glucose sensitive promoter, beta-farnesene synthase is mutated and fused with a transmembrane structural domain of ABC transporter protein PDR10, and then a chimeric expression unit is constructed. According to the present invention, the chassis bacteria are modified by at least one of the steps of overexpression of phosphatidylcholine synthetase, knockout of sterol ester synthetase and introduction of exogenous alkyl glycerol monooxygenase, and the obtained engineering bacteria are combined with the optimized fermentation process so as to significantly improve the farnesene synthesis efficiency and the production economy; therefore, the genetically engineered bacterium and the fermentation method provided by the invention have good application prospects.

The application discloses a kind of generation (4S) 4-hydroxyisophorone monooxygenase mutant and preparation method thereof, the monooxygenase is cytochrome P450 BM3 Monooxygenase from bacillus megaterium. The cytochrome P450 BM3 Monooxygenase mutant has high stereoselectivity and high reaction activity to catalyze isophorone hydroxylation, mutant R47L / Y51F / F81W / A191T / N239H / I259V / A276T / A328I / A330S / L353I / I401L / L437LL catalyzes isophorone to obtain (4S) 4-hydroxyisophorone diastereomeric excess rate can reach 95%, yield can reach 96%; the cytochrome P450 BM3 Monooxygenase mutant catalyzes isophorone synthesis (4S) 4-hydroxyisophorone process is simple, environmental protection, and industrialization prospect is good.

The invention discloses 10-hydroxydecanoic acid as well as a preparation method and application thereof, and belongs to the technical field of cosmetics, Candida lipolytica is taken as a fermentation thallus, the Candida lipolytica contains alkane monooxygenase (CYP450), alcohol dehydrogenase (ADH), fatty alcohol oxidase (FAO) and fatty aldehyde dehydrogenase (FALDH), amplification and activation are performed on the Candida lipolytica in a seed culture medium, and the Candida lipolytica is obtained. The method comprises the following steps: inoculating a seed solution into a liquid culture medium, enabling a strain to adapt to a culture environment in advance, reducing strain death caused by environmental mutation after inoculation, inoculating the seed solution into the liquid culture medium, culturing until OD600 is 45-55, realizing high-density enrichment of the strain, being beneficial to increasing the content of CYP450, ADH, FAO and FALDH, adding decane and Tween 80, and enabling the Tween 80 to be capable of increasing the permeability of a cell membrane and increasing the reaction rate, the CYP450 is used for catalyzing decane to carry out hydroxylation, and ADH, FAO and FALDH are used for carrying out oxidation, so that the high-purity 10-hydroxydecanoic acid is obtained.

The present invention relates to a cytochrome P450 monooxygenase mutant and its application in hydroxylation of methylpyrazine compounds, belonging to the technical field of enzyme engineering. The amino acid sequence of the cytochrome P450 monooxygenase mutant provided by the present invention is shown in SEQ ID NO.2. The cytochrome P450 monooxygenase mutant L76S / A83E provided by the present invention exhibits hydroxylation activity towards methylpyrazine substrates, and the reaction conversion rate is greater than or equal to 95%, achieving a breakthrough in the catalytic activity of cytochrome P450 monooxygenase from non-existent to existent. Therefore, the cytochrome P450 monooxygenase and its gene described in the present invention have good prospects for industrial application development.

The invention discloses 4-hydroxy-3-methyl benzoic acid monooxygenase, a strain and a preparation method and application thereof, and relates to the technical field of bioengineering, the nucleotide sequence of the 4-hydroxy-3-methyl benzoic acid monooxygenase is shown as SEQ ID NO: 1, and the amino acid sequence of the 4-hydroxy-3-methyl benzoic acid monooxygenase is shown as SEQ ID NO: 2 and / or SEQ ID NO: 3. The gene of the 4-hydroxy-3-methyl benzoic acid monooxygenase disclosed by the invention can be used for encoding to obtain the 4-hydroxy-3-methyl benzoic acid monooxygenase, and the obtained 4-hydroxy-3-methyl benzoic acid monooxygenase can be used for effectively catalyzing continuous oxidation of ortho-methyl of hydroxyl in 4-hydroxy-3-methyl benzoic acid; the selective continuous oxidation of the ortho-position methyl of the 4-hydroxy-3-methylbenzoic acid can be realized, the 4-hydroxyisophthalic acid is generated, and the compound 4-hydroxyisophthalic acid with industrial added value is synthesized while the selective oxidation of the methyl is solved.

This invention relates to increasing the level of peptidyl glycine α-amidyl monooxygenase (PAM) in human circulation as a long-acting drug and for treating subjects, wherein said treatment includes: reducing the likelihood or risk of disease or condition, and / or reducing the occurrence of disease or condition, and / or reducing the severity of disease or condition.

The invention provides a compound enzyme preparation and application thereof, and belongs to the technical field of compound enzymes. The complex enzyme preparation is composed of the soluble polysaccharide monooxygenase, the hemicellulase and the trivalent rare earth metal ions, has high stability and high activity, and can reduce the use amount of the enzyme in the enzymatic hydrolysis process of the lignocellulose material, so that the yield of the lignocellulose material is increased. The enzymolysis efficiency of the lignocellulose material is improved; and the production cost of preparing a sugar product from the lignocellulose material is reduced.

The application discloses a method for promoting transport and improving retinal synthesis, which is obtained by introducing an exogenous ABC transport protein Pdr5 into a host fungus and adding a copy of beta-carotene-15, 15'-monooxygenase BLH; wherein the host fungus is a genetically modified Pichia pastoris strain PP-BCCIV. The application further verifies the retinal production performance of the recombinant strain by screening different surfactants, and further improves the ability of Pichia pastoris to produce retinal. At the same time, all the retinal is extracted into the extracellular, and all the carotenes are left in the intracellular, so as to achieve the co-production of carotenes and retinal. The recombinant Pichia pastoris of the application has a simple construction method, can better promote the synthesis of retinal and other vitamin A, and can make the engineering strain utilize glucose and methanol to efficiently synthesize retinal through a 5 L fermentation tank, which is beneficial to industrial production.

The invention relates to the field of genetic engineering and fermentation engineering, and discloses a genetically engineered bacterium for producing melatonin and application of the genetically engineered bacterium in fermentation production of melatonin. According to the invention, genes of mtrA, PTPS, SPR, PCD and DHPR of related enzymes synthesized by coding 2-amino-6-(1, 2-dihydroxypropyl)-5, 6, 7, 8-tetrahydro-4 (1H)-pterin diketone and genes of L-2-amino-3 (beta-indole) propionic acid monooxygenase, oxymethyltransferase, N-acetyltransferase and decarboxylase are co-expressed on the genetically engineered bacterium, so that the gene engineering bacterium is obtained. The strain can be used for fermentation production of melatonin, and experiments show that the yield of the strain can reach 6480 mg / L.

The invention provides a multienzyme system for preparing cellobiose as well as a preparation method and application of cellobiose, and belongs to the technical field of bioengineering. The multi-enzyme system disclosed by the invention is prepared from endoglucanase, cellobiose hydrolase and lysed polysaccharide monooxygenase, wherein the endoglucanase is EG5C-1m, the cellobiose hydrolase is TeCel7A T393K, and the lysed polysaccharide monooxygenase is LsAA9A. According to the method disclosed by the invention, a multi-enzyme system for accurately degrading cellulose into cellobiose is constructed by screening high-efficiency endoglucanase, cellobiose hydrolase and lysed polysaccharide monooxygenase. On the basis, the optimal reaction condition of a multi-enzyme system is determined, a method is provided for efficient generation of cellobiose from cellulose, and a basis is provided for subsequent biomass conversion of high-value products.

This invention relates to the field of biomedicine, and discloses the application of flavin-containing monooxygenase 2 in the preparation of drugs for the treatment of non-alcoholic fatty liver disease. This invention is the first to discover that flavin-containing monooxygenase 2 has a preventive or therapeutic effect on non-alcoholic fatty liver disease.

The invention discloses a monooxygenase gene bpfC, an enzyme coded by the monooxygenase gene bpfC and application of the monooxygenase gene bpfC. The strain DN12 is separated and can degrade the BPF and grow by taking the BPF as the unique carbon source and energy. On the basis, a BPF degradation gene cluster bpf is obtained from the strain DN12 by adopting whole genome and comparative transcriptome sequencing analysis. Three different degrading enzymes (two-component oxidase BpfAB, monooxygenase BpfC and hydrolase BpfD) are found in the gene cluster and can catalyze gradual degradation of BPF, and a simple aromatic ring compound p-hydroxybenzoic acid is generated.

The application relates to the technical field of wheat kernel type genes, and provides a wheat kernel type gene TaCYT-5A TaCYT-5A The application of the molecular marker is KASP-TaCYT-5A, the marker is a SNP site (C / T) detected at 495818646 bp in a QTL cluster for controlling the wheat kernel type and kernel length traits of a 5A chromosome 484432128-495883712 bp, that is, a 4-hydroxyphenylacetaldehyde oxime monooxygenase gene TaCYT-5A The coding region is 124 bp away from the start codon. The functional KASP molecular marker of the wheat 4-hydroxyphenylacetaldehyde oxime monooxygenase gene TaCYT-5A provided by the application can be used for identifying whether an TaCYT-5A excellent allele exists in a wheat variety / strain, and applied in assisted selection breeding and breeding in combination with other known kernel type related genes.

The invention belongs to the technical field of biological catalysis and biological engineering, and relates to a lytic polysaccharide monooxygenase expression system and application thereof. The expression system comprises an expression vector containing a lysing polysaccharide monooxygenase gene expression cassette and a host, the host is a pyrG auxotroph type aspergillus niger strain. According to the present invention, the deltaglaA gene knockout pyrG auxotrophic aspergillus niger strain is adopted as the host, and the strong promoter GlaPr is introduced to drive the expression of the cellulose activity LPMO gene, such that the interference of the endogenous glucamylase is eliminated, and the LPMO secretion efficiency is enhanced; a dynamic fermentation process is adopted, and efficient production of the LPMO protein is achieved.

The invention discloses a plurality of BVMO or mutants thereof, the BVMO or the mutants thereof can be used for effectively catalyzing 5-chloro-1-oxo-2, 3-dihydro-1H-indene-2-carboxylic acid methyl ester to generate (S)-5-chloro-2, 3-dihydro-2-hydroxy-1-oxo-1H-indene-2-carboxylic acid methyl ester, and the (S)-5-chloro-2, 3-dihydro-2-hydroxy-1-oxo-1H-indene-2-carboxylic acid methyl ester can be used for catalyzing 5-chloro-1-oxo-2, 3-dihydro-1H-indene-2-carboxylic acid methyl ester to generate (S)-5-chloro-2, 3-dihydro-2-hydroxy-1-oxo-1H-indene-2-carboxylic acid methyl ester. The conversion rate and the optical purity of the 2, 3-dihydro-2-hydroxy-1-oxo-1H-indene-2-carboxylic acid methyl ester can reach 99%, and excellent catalytic effect and conversion efficiency are shown. The indoxacarb intermediate is prepared by adopting a biological catalysis method, so that the production cost can be greatly reduced, the problem of environmental pollution can be avoided, and the indoxacarb intermediate has a wide application prospect and a high market value.

The present invention relates to compounds of formula (I) wherein A is a 3-10 membered carbocyclic ring or a 4-12 membered heterocyclic ring containing 1-4 heteroatoms selected from O, N or S; B is any one of the following groups (1), (2) or (3); C is any one of the following groups (1'), (2'), (3') or (4'); G1 is CH2, NH or O; G2 and G3 are independently of each other CH or N; Z is -C(O)-, -SO2-, -C 1‑3 alkyl- or -CH2-C(O)-; L is a bond, -C 1‑7 alkyl- or -C 1‑7 alkenyl-. The compounds of formula (I) are inhibitors of cytochrome P450 monooxygenase 11A1 (CYP11A1). The compounds are useful as medicaments for the treatment of steroid receptor, e.g. androgen receptor or estrogen receptor dependent diseases and disorders such as cancer including prostate cancer and estrogen cancer.

The present application provides a kind of cytochrome P450 monooxygenase gene and the protein coded by it, recombinant plasmid and application derived from ramie, the coding region sequence of the cytochrome P450 monooxygenase gene derived from ramie is as shown in SEQ ID NO:1, the amino acid sequence of the protein coded by it is as shown in SEQ ID NO:2.The present application takes ramie as research object, obtains ramie cytochrome P450 monooxygenase gene (BnMAX1) by three generations sequencing and gene annotation comparison.Longer coding sequence of the target gene is obtained by PacBio Sequel sequencing, which is simple, fast and easy to operate.The function of the gene is verified by cloning identification, bioinformatics, expression pattern and genetic transformation analysis, which shows that the gene has the effect of relieving plant cadmium toxicity.The acquisition and application of the gene provide basic theoretical support for molecular improvement of cadmium tolerance of ramie, and provide new technical means for how to improve the ecological restoration ability of ramie under heavy metal cadmium stress.

本发明涉及微生物菌肥技术领域，特别是涉及一种菌酶复合微生物菌剂及其制备方法和应用。本发明针对田间秸秆还田腐解慢、影响下茬作物生长的问题，提供了一种菌酶复合微生物菌剂。所述菌酶复合微生物菌剂由草酸青霉（Penicillium oxalicum）菌株F12的孢子悬液与裂解性多糖单加氧酶（LPMO）按特定配比复配而成。田间施用时，将秸秆粉碎抛撒后，通过无人机喷洒菌剂，翻压入土，并调节土壤相对湿度。本发明解决了秸秆腐解慢的技术难题，有助于促进种子出苗和减少病虫害发生，可在秸秆还田场景和菌剂生产企业中推广应用。

The invention relates to cold-resistant pseudoarthrobacter LH-LT-1 resistant to heavy metal stress and low temperature as well as a microbial agent and application thereof, and belongs to the technical field of microorganisms. The cold-resistant pseudoarthrobacter LH-LT-1 is classified and named as Pseudarthrobacter psychrotolerans, and the preservation number of the cold-resistant pseudoarthrobacter LH-LT-1 is CGMCC (China General Microbiological Culture Collection Center) No. 32708. The cold-tolerant pseudoarthrobacter LH-LT-1 can amplify gene sequences of ammonia monooxygenase, hydroxylamine oxidoreductase and the like based on gene primers of amoA, hao and the like, and can amplify gene sequences of cold shock protein, cold shock protein, ATP binding protein, excision nuclease and the like based on gene primers of Csp4, cspA II, atpH, uvrC and the like. The strain can tolerate multiple heavy metal ions such as Pb < 2 + >, Ni < 2 + > and Cd < 2 + >, can efficiently reduce ammonia nitrogen under the stress of cadmium ions at 5 DEG C, and provides an efficient and low-cost biological solution for reducing ammonia nitrogen in sewage and wastewater at low temperature of 5 DEG C under the stress of a series of heavy metals represented by cadmium.