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1.
Screening of a wide range of microorganisms (32 strains) isolated from various anthropogenic and natural environments and of a number of collection strains showed that the early stages of 2,4,6-trinitrotoluene (TNT) transformation by the majority of the strains studied resulted in the formation of hydroxylaminodinitrotoluenes (HADNTs). The levels of HADNTs were in a number of cases comparable to the initial TNT level. The alternative reductive attack at TNT through the reduction of the aromatic ring was not characteristic of most of the prokaryotes studied. The susceptibility to the toxic effect of TNT was different for gram-positive and gram-negative bacteria. 相似文献
2.
Galina K. Vasilyeva Byung-Taek Oh Patrick J. Shea Rhae A. Drijber Vladimir D. Kreslavski Robert Minard Jean-Marc Bollag 《Bioremediation Journal》2000,4(2):111-124
Bioremediation of munitions-contaminated soil requires effective transformation and detoxification of high concentrations of 2,4,6-trinitrotoluene (TNT). Pseudomonas aeruginosa strain MX, isolated from munitions-contaminated soil, aerobically transformed TNT (100 mg/L) in culture medium within 15 h, causing transient accumulation of hydroxylaminodinitrotoluenes (HADNTs). The predominance of 2-hydroxylamino-4,6-dinitrotoluene (2HADNT), as well as 2-amino-4,6-dinitrotoluene (2ADNT) and 4,4' ,6,6' -tetranitro-2,2' -azoxytoluene (2,2'AZT), indicated preferential reduction of the TNT ortho nitro group. While only 12% of the TNT was transformed to 2ADNT, up to 65% was transformed to tetranitroazoxytoluenes (AZTs), which accumulated as a precipitate. The precipitate was formed by microscopic particles adhering to bacterial cells, which subsequently formed clusters containing lysed cells. Toxicity toward bacteria was primarily attributed to 2ADNT, because pure AZTs preincubated with sterile medium had little effect on the strain. While the culture medium containing TNT exhibited toxicity toward corn (Zea mays L.) and witchgrass (Panicum capillare L.), little phytotoxicity was observed after incubating with P. aeruginosa strain MX for 4 d. Strong binding of HADNTs to soil and low AZT bioavailability may further promote the detoxification of TNT in soil. 相似文献
3.
Successful microbial-mediated remediation requires transformationpathways that maximize metabolism and minimize the accumulation of toxic products. Pseudomonas aeruginosa strain MX, isolated from munitions-contaminated soil, degraded 100 mg TNT L-1 in culture medium within 10 h under aerobic conditions. The major TNT products were 2-amino-4,6-dinitrotoluene (2ADNT, primarily in the supernatant) and 2,2'-azoxytoluene (2,2'AZT, primarily in the cell fraction), which accumulated as major products via the intermediate2-hydroxylamino-4,6-dinitrotoluene (2HADNT). The 2HADNT and2,2'AZT were relatively less toxic to the strain than TNT and 2ADNT. Aminodinitrotoluene (ADNT) production increased when yeast extract was added to the medium. While TNT transformation rate was not affected by pH, more HADNTs accumulated at pH 5.0 than at pH 8.0 and AZTs did not accumulate at the lower pH. The appearance of 2,6-diamino-4-nitrotoluene (2,6DANT) and 2,4-diamino-6-nitrotoluene (2,4DANT); dinitrotoluene (DNT) and nitrotoluene (NT); and 3,5-dinitroaniline (3,5DNA) indicated various routes of TNT metabolism and detoxification by P. aeruginosa strain MX. 相似文献
4.
Biotransformation of 2,4,6-trinitrotoluene with Phanerochaete chrysosporium in agitated cultures at pH 4.5. 总被引:1,自引:0,他引:1
J Hawari A Halasz S Beaudet L Paquet G Ampleman S Thiboutot 《Applied and environmental microbiology》1999,65(7):2977-2986
The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 microM) by Phanerochaete chrysosporium with molasses and citric acid at pH 4.5 was studied. In less than 2 weeks, TNT disappeared completely, but mineralization (liberated 14CO2) did not exceed 1%. A time study revealed the presence of several intermediates, marked by the initial formation of two monohydroxylaminodinitrotoluenes (2- and 4-HADNT) followed by their successive transformation to several other products, including monoaminodinitrotoluenes (ADNT). A group of nine acylated intermediates were also detected. They included 2-N-acetylamido-4,6-dinitrotoluene and its p isomer, 2-formylamido-4, 6-dinitrotoluene and its p isomer (as acylated ADNT), 4-N-acetylamino-2-amino-6-nitrotoluene and 4-N-formylamido-2-amino-6-nitrotoluene (as acetylated DANT), 4-N-acetylhydroxy-2,6-dinitrotoluene and 4-N-acetoxy-2, 6-dinitrotoluene (as acetylated HADNT), and finally 4-N-acetylamido-2-hydroxylamino-6-nitrotoluene. Furthermore, a fraction of HADNTs were found to rearrange to their corresponding phenolamines (Bamberger rearrangement), while another group dimerized to azoxytoluenes which in turn transformed to azo compounds and eventually to the corresponding hydrazo derivatives. After 30 days, all of these metabolites, except traces of 4-ADNT and the hydrazo derivatives, disappeared, but mineralization did not exceed 10% even after the incubation period was increased to 120 days. The biotransformation of TNT was accompanied by the appearance of manganese peroxidase (MnP) and lignin-dependent peroxidase (LiP) activities. MnP activity was observed almost immediately after TNT disappearance, which was the period marked by the appearance of the initial metabolites (HADNT and ADNT), whereas the LiP activity was observed after 8 days of incubation, corresponding to the appearance of the acyl derivatives. Both MnP and LiP activities reached their maximum levels (100 and 10 U/liter, respectively) within 10 to 15 days after inoculation. 相似文献
5.
The sensitivity of Escherichia coli strains K-12 and 055 to 2,4,6-trinitrotoluene (TNT) was found to correlate with the structural and functional properties of the outer lipoprotein membrane. The protective ability of the membrane of strain 055 is much lower than that of K-12. This is the cause of the greater sensitivity of 055 to the toxic action of TNT. High TNT concentrations (100-200 mg/l) suppressed the growth of 055, whereas K-12 grew at all TNT concentrations studied. Both strains adapted to high TNT concentrations by converting it by either nitroreduction or denitritation depending on concentration. The denitritation system of strain 055 started TNT degradation earlier than that of K-12. 相似文献
6.
Anaerobic bacteria have been used to produce 2,4-dihydroxylamino-nitrotoluene (2,4DHANT), a reductive metabolite of 2,4,6-trinitrotoluene
(TNT). Here, an aerobic TNT biodegrader Pseudomonas sp. strain TM15 produced 2,4DHANT as evidenced by the molecular ion with m/z of 199 identified from LC-TOFMS analyses. TNT
biodegradation with a high cell concentration (109 cells/ml) led to a significant accumulation of 2,4DHANT in the culture medium, as well as hydroxylamino-dinitrotoluenes (HADNTs),
although these products were not accumulated when a low cell concentration was used; also, the accumulation of diamino-nitrotoluene
and of an unidentified metabolite were observed in the culture medium with the high cell concentration (1010 cells/ml). 2,4DHANT overproduction was a function of the aeration speed since cultures with low aeration speeds (30 rpm)
had a 19-fold higher DHANT productivity than those aerated with high speeds (180 rpm); this indicates that molecular oxygen
was related to the formation of 2,4DHANT. The quantification of dissolved oxygen (DO) in the media demonstrated that the productivity
of 2,4DHANT was increased at low DO values. Moreover, supplying oxygen to the culture media produced a remarkable decrease
of 2,4DHANT accumulation; these results clearly indicate that high 2,4DHANT production was a consequence of the oxygen deficit
in the culture medium. This finding is useful for understanding the TNT biodegradation (bioremediation technology) in an anoxic
environment.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
B. M. Kurinenko N. A. Denivarova G. Yu. Yakovleva 《Applied Biochemistry and Microbiology》2005,41(1):47-50
The sensitivity of Escherichia coli strains K-12 and 055 to 2,4,6-trinitrotoluene (TNT) was found to correlate with the structural and functional properties of the outer lipoprotein membrane. The protective ability of the membrane of strain 055 is much lower than that of K-12. This is the cause of the greater sensitivity of 055 to the toxic action of TNT. High TNT concentrations (100–200 mg/l) suppressed the growth of 055, whereas K-12 grew at all TNT concentrations studied. Both strains adapted to high TNT concentrations by converting it by either nitroreduction or denitritation depending on concentration. The denitritation system of strain 055 started TNT degradation earlier than that of K-12.Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 1, 2005, pp. 53–57.Original Russian Text Copyright © 2005 by Kurinenko, Denivarova, Yakovleva. 相似文献
8.
Biotransformation of 2,4,6-Trinitrotoluene with Phanerochaete chrysosporium in Agitated Cultures at pH 4.5
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Jalal Hawari Annamaria Halasz Sylvie Beaudet Louise Paquet Guy Ampleman Sonia Thiboutot 《Applied microbiology》1999,65(7):2977-2986
The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 μM) by Phanerochaete chrysosporium with molasses and citric acid at pH 4.5 was studied. In less than 2 weeks, TNT disappeared completely, but mineralization (liberated 14CO2) did not exceed 1%. A time study revealed the presence of several intermediates, marked by the initial formation of two monohydroxylaminodinitrotoluenes (2- and 4-HADNT) followed by their successive transformation to several other products, including monoaminodinitrotoluenes (ADNT). A group of nine acylated intermediates were also detected. They included 2-N-acetylamido-4,6-dinitrotoluene and its p isomer, 2-formylamido-4,6-dinitrotoluene and its p isomer (as acylated ADNT), 4-N-acetylamino-2-amino-6-nitrotoluene and 4-N-formylamido-2-amino-6-nitrotoluene (as acetylated DANT), 4-N-acetylhydroxy-2,6-dinitrotoluene and 4-N-acetoxy-2,6-dinitrotoluene (as acetylated HADNT), and finally 4-N-acetylamido-2-hydroxylamino-6-nitrotoluene. Furthermore, a fraction of HADNTs were found to rearrange to their corresponding phenolamines (Bamberger rearrangement), while another group dimerized to azoxytoluenes which in turn transformed to azo compounds and eventually to the corresponding hydrazo derivatives. After 30 days, all of these metabolites, except traces of 4-ADNT and the hydrazo derivatives, disappeared, but mineralization did not exceed 10% even after the incubation period was increased to 120 days. The biotransformation of TNT was accompanied by the appearance of manganese peroxidase (MnP) and lignin-dependent peroxidase (LiP) activities. MnP activity was observed almost immediately after TNT disappearance, which was the period marked by the appearance of the initial metabolites (HADNT and ADNT), whereas the LiP activity was observed after 8 days of incubation, corresponding to the appearance of the acyl derivatives. Both MnP and LiP activities reached their maximum levels (100 and 10 U/liter, respectively) within 10 to 15 days after inoculation. 相似文献
9.
Broad screening of microorganisms from natural and anthropogenic ecological niches has revealed strains Candida sp. AN-L15 and Geotrichum sp. AN-Z4 which transform 2,4,6-trinitrotoluene (TNT) via alternative pathways (with the domination of hydride ion-mediated reduction of the aromatic ring) and produce relatively high amounts of nitrites. According to the spectrophotometry data, the hydride attack of TNT by Candida sp. AN-L15 and Geotrichum sp. AN-Z4 grown at pH 5.0-8.0 leads to the mono- and dihydride complexes of TNT (H(-)-TNT and 2H(-)-TNT, respectively) and to protonated forms of the latter. Analysis by HPLC, GC-mass spectrometry, and ion chromatography revealed the products of deep conversion of TNT. The growth of the yeast strains in a weakly acidic medium with TNT (440 microM) is accompanied by formation of 2,4-dinitrotoluene (2,4-DNT, up to 18.2 microM). Together with accumulation of nitrites (up to 76.0 microM, depending on pH of the medium), these findings demonstrate the capacity of both strains for TNT denitration. Formation of 2,4-DNT reflects the realization of one of the possible mechanisms of TNT ortho-nitro group elimination and switching over to the pathways of metabolism of dinitrotoluenes, which are much more easily biodegradable than TNT. Simultaneously with the dominating TNT hydride attack, the mechanism of 4- and 6-electron reduction of the nitro group also functions in Candida sp. AN-L15 and Geotrichum sp. AN-Z4. Realization of the studied mechanisms of TNT transformation under growth of Candida sp. AN-L15 on n-alkane is important for bioremediation in the cases of combined pollution by oil products and explosives. 相似文献
10.
Transformation of 2,4,6-trinitrotoluene (TNT) by actinomycetes isolated from TNT-contaminated and uncontaminated environments.
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Actinomycete strains isolated from 2,4,6-trinitrotoluene (TNT)-contaminated and uncontaminated environments were compared for TNT tolerance and abilities to transform TNT. Regardless of previous TNT exposure history, no significant differences in TNT tolerance were seen among strains. Selected strains did not significantly mineralize [14C]TNT. The actinomycetes did, however, transform TNT into reduced intermediates. The data indicate that, in actinomycete-rich aerobic environments like composts, actinomycetes will transform TNT into intermediates which are known to form recalcitrant polymers. 相似文献
11.
Solianikova IP Baskunov BP Baboshin MA Saralov AI Golovleva LA 《Prikladnaia biokhimiia i mikrobiologiia》2012,48(1):27-34
The ability of the strains-destructors of various aromatic compounds to utilize trinitrotoluene (TNT) up to concentration of 70 mg/1 was shown. An increase in the TNT concentration from 100 to 150 mg/1 did not inhibit its conversion rate by the Kocuria palustris RS32 strain. The Acinetobacter sp. VT 11 strain utilized TNT as a sole substrate for growth; 3,5-dinitro-4-methyl anilide acetate and 2,6-dinitro-4-aminotoluene were identified as intermediates of TNT degradation by active strains of Pseudomonas sp. VT-7W and Kocuria rosea RS51. At the same time, 4-methyl-3,5-dinitroformamide was discovered for the first time upon the TNT destruction by the bacteria strains of Rhodococcus opacus 1G and Rhodococcus sp. VT-7. The active bacterial strains achieved an 82-90% destruction of TNT when they were introduced into the soil. 相似文献
12.
Khachatryan G.E. Mkrtchyan N.I. Simonyan N.V. Khachatryan T.V. Tatikyan S.Sh. 《World journal of microbiology & biotechnology》2000,16(4):393-395
Several strains of aerobic bacteria tolerant to some chemical toxins were isolated from the water of man-made Yerevan Lake and from the soil and air of different regions of the city of Yerevan. Some of these bacteria were capable of degrading 2,4,6-trinitrotoluene (TNT) during shake-flask fermentation in liquid medium. Two bacterial strains with good ability to degrade TNT were isolated. These strains showed visible morphological and physiological differences during growth on numerous elective media. The comparative ability of these strains to transform TNT was investigated. 相似文献
13.
M M Ederer T A Lewis R L Crawford 《Journal of industrial microbiology & biotechnology》1997,18(2-3):82-88
Several bacterial strains were examined for their ability to degrade the nitroaromatic explosive 2,4,6-trinitrotoluene (TNT).
The strains examined included various clostridial strains isolated from a 4-year-old munition enrichment, related clostridial
strains obtained from a culture collection, two enteric bacteria, and three lactobacilli. All Clostridium species tested were able to reduce TNT rapidly in a complex medium. In cell suspension experiments, these strains were
also able to reduce 2,4-diamino-6-nitrotoluene (DANT) to 2,4,6-triaminotoluene (TAT) and to produce a compound that is not
yet identified; thus, they could not be distinguished from one another with regard to the pathway of transformation. The
enteric strains and the lactobacilli were able to perform the initial reduction of TNT, but none was capable of reducing
DANT in cell suspensions.
Received 31 October 1995/ Accepted in revised form 29 March 1996 相似文献
14.
Chih-Ming Kao Bo-Hsin Lin Ssu-Ching Chen Shih-Feng Wei Chien-Cheng Chen Chao-Ling Yao 《Bioremediation Journal》2016,20(3):165-173
Soil and groundwater contaminated by munitions compounds is a crucial issue in environmental protection. Trinitrotoluene (TNT) is highly toxic and carcinogenic; therefore, the control and remediation of TNT contamination is a critical environmental issue. In this study, the authors characterized the indigenous microbial isolates from a TNT-contaminated site and evaluated their activity in TNT biodegradation. The bacteria Achromobacter sp. BC09 and Citrobacter sp. YC4 isolated from TNT-contaminated soil by enrichment culture with TNT as the sole carbon and nitrogen source (strain BC09) and as the sole nitrogen but not carbon source (strain YC4) were studied for their use in TNT bioremediation. The efficacy of degradation of TNT by indigenous microorganisms in contaminated soil without any modification was insufficient in the laboratory-scale pilot experiments. The addition of strains BC09 and YC4 to the contaminated soil did not significantly accelerate the degradation rate. However, the addition of an additional carbon source (e.g., 0.25% sucrose) could significantly increase the bioremediation efficiency (ca. decrease of 200 ppm for 10 days). Overall, the results suggested that biostimulation was more efficient as compared with bioaugmentation. Nevertheless, the combination of biostimulation and bioaugmentation using these indigenous isolates is still a feasible approach for the development of bioremediation of TNT pollution. 相似文献
15.
P Einist? 《Mutation research》1991,262(3):167-169
The urine mutagenicity of rats exposed to 2,4,6-trinitrotoluene (TNT) by i.p. injection was studied in the Salmonella assay using indicator strains with various levels of 'classical' nitroreductase or acetyl-CoA:N-hydroxylarylamine O-acetyltransferase activity. The strains used were the conventional Salmonella typhimurium TA98, nitroreductase-deficient TA98NR and -overproducing YG1021, and O-acetyltransferase-deficient TA98/1,8-DNP6 and -overproducing YG1024. TA98, YG1021 and YG1024 clearly detected the increase of direct urine mutagenicity. A slight increase of mutagenicity was also detected with metabolic activation in YG1021 and YG1024. High levels of both nitroreductase and O-acetyltransferase significantly increased the sensitivity of the indicator strain to the mutagenicity of urine caused by TNT exposure, while the nitroreductase- or O-acetyltransferase-deficient strains gave negative responses. 相似文献
16.
2,4,6-trinitrotoluene reduction by an Fe-only hydrogenase in Clostridium acetobutylicum 总被引:1,自引:0,他引:1
Watrous MM Clark S Kutty R Huang S Rudolph FB Hughes JB Bennett GN 《Applied and environmental microbiology》2003,69(3):1542-1547
The role of hydrogenase on the reduction of 2,4,6-trinitrotoluene (TNT) in Clostridium acetobutylicum was evaluated. An Fe-only hydrogenase was isolated and identified by using TNT reduction activity as the selection basis. The formation of hydroxylamino intermediates by the purified enzyme corresponded to expected products for this reaction, and saturation kinetics were determined with a K(m) of 152 micro M. Comparisons between the wild type and a mutant strain lacking the region encoding an alternative Fe-Ni hydrogenase determined that Fe-Ni hydrogenase activity did not significantly contribute to TNT reduction. Hydrogenase expression levels were altered in various strains, allowing study of the role of the enzyme in TNT reduction rates. The level of hydrogenase activity in a cell system correlated (R(2) = 0.89) with the organism's ability to reduce TNT. A strain that overexpressed the hydrogenase activity resulted in maintained TNT reduction during late growth phases, which it is not typically observed in wild type strains. Strains exhibiting underexpression of hydrogenase produced slower TNT rates of reduction correlating with the determined level of expression. The isolated Fe-only hydrogenase is the primary catalyst for reducing TNT nitro substituents to the corresponding hydroxylamines in C. acetobutylicum in whole-cell systems. A mechanism for the reaction is proposed. Due to the prevalence of hydrogenase in soil microbes, this research may enhance the understanding of nitroaromatic compound transformation by common microbial communities. 相似文献
17.
降解三硝基甲苯的酵母和类酵母菌的研究 总被引:9,自引:0,他引:9
从受三硝基甲苯(TNT)严重污染的土壤和废水中分离筛选到17株可降解TNT的酵母菌和白地霉。其中6株为克鲁斯假丝酵母(Candidakrusei),4株为橡树假丝酵母(C.quercitrusa),一株为无名假丝酵母(C.famata),一株为伯杰汉逊酵母(Hansenulabeijerinckii),一株为亚膜汉逊酵母(H.subpelliculosa),4株为白地霉(Geotrichumcandidum)。对其中6株菌进行了降解TNT的条件实验,发现降解TNT的适宜pH为7,温度为37~40℃。在含75~80mg/LTNT的培养基中,40h内能降解TNT56~74mg/L,去除率达71%~93%。在培养基中加入0.01%~0.05%的葡萄糖作碳源,或加入0.01%~0.1%的酵母膏对6株菌降解TNT的能力略有促进作用。加入铵盐作为氮源则明显抑制这些菌对TNT的降解。 相似文献
18.
A. M. Ziganshin A. V. Naumov E. S. Suvorova E. A. Naumenko R. P. Naumova 《Microbiology》2007,76(6):676-682
Broad screening of microorganisms from natural and anthropogenic ecological niches has revealed strains Candida sp. AN-L15 and Geotrichum sp. AN-Z4 which transform, 2,4,6-trinitrotoluene (TNT) via alternative pathways (with the domination of hydride ion-mediated reduction of the aromatic ring) and produce relatively high amounts of nitrites. According to the spectrophotometry data, the hydride attack of TNT by Candida sp. AN-L15 and Geotrichum sp. AN-Z4 grown at pH 5.0–8.0 leads to the mono-and dihydride complexes of TNT (H?-TNT and 2H?-TNT, respectively) and to protonated forms of the latter. Analysis by HPLC, GC-mass spectrometry, and ion chromatography revealed the products of deep conversion of TNT. The growth of the yeast strains in a weakly acidic medium with TNT (440 μM) is accompanied by formation of 2,4-dinitrotoluene (2,4-DNT, up to 18.2 μM). Together with accumulation of nitrites (up to 76.0 μM, depending on pH of the medium), these findings demonstrate the capacity of both strains for TNT denitration. Formation of 2,4-DNT reflects the realization of one of the possible mechanisms of TNT ortho-nitro group elimination and switching over to the pathways of metabolism of dinitrotoluenes, which are much more easily biodegradable than TNT. Simultaneously with the dominating TNT hydride attack, the mechanism of 4-and 6-electron reduction of the nitro group also functions in Candida sp. AN-L15 and Geotrichum sp. AN-Z4. Realization of the studied mechanisms of TNT transformation under growth of Candida sp. AN-L15 on n-alkane is important for bioremediation in the cases of combined pollution by oil products and explosives. 相似文献
19.
Three strains, T10, B5, and M8, each belonging to a different species of the family Rhizobiaceae and isolated from atrazine-contaminated soils, were tested for their ability to transform 2,4,6-trinitrotoluene (TNT) (50 microg x mL(-1)) in liquid cultures using glucose as the C-source. All three strains were able to transform TNT to hydroxylaminodinitrotoluenes (2-HADNT, 4-HADNT), aminodinitrotoluenes (2-ADNT, 4-ADNT), and diaminonitrotoluene (2,4-DANT). The transformation was significantly faster in the presence of glutamate. Furthermore, the major metabolites that accumulated in cultures were 2-ADNT with glucose, and 4-ADNT with glutamate plus glucose. Rhizobium trifolii T10 was also tested for its ability to transform high levels of TNT (approximately 350 microg x mL(-1)) in a soil slurry. Almost 60% of the TNT was transformed within 2 days in bioaugmented soil slurries, and up to 90% when cultures were supplemented with glucose and glutamate. However, mineralization was minimal in all cases, less than 2% in 78 days. This is the first report on the degradation of TNT by rhizobial strains, and our findings suggest that rhizobia have the potential to play an important role in the safe decontamination of soils and sites contaminated with TNT if bioaugmentation with rhizobia is shown to have no ecotoxicological consequence. 相似文献
20.
The degradation of 2,4,6-trinitrotoluene (TNT) by seven strains of white rot fungi was examined in two different media containing
50 mg L−1 of TNT. When TNT was added into a nutrient-rich YMG medium at the beginning of the incubation, four of the fungal strains
completely removed TNT during several days of incubation and showed higher removal rates than those of Phanerochaete chrysosporium. TNT added into YMG medium after a 5-day preincubation period completely disappeared within 12 hours, and the removal rates
were higher than those in N-limited minimal medium. Isomers of hydroxylamino-dinitrotoluene were identified as the first detectable
metabolites of TNT. These were transformed to amino-dinitrotoluenes, which also disappeared during further incubation from
cultures of Irpex lacteus. During the initial phase of TNT degradation by I. lacteus, dinitrotoluenes were also detected after the transient formation of a hydride-Meisenheimer complex, indicating that I. lacteus used two different pathways of TNT degradation simultaneously.
Received: 29 March 2000 / Accepted: 23 May 2000 相似文献