Multi-year and multi-site effects of recurrent glyphosate applications on the wheat rhizosphere microbiome.

Glyphosate (N-(phosphonomethyl)glycine) is broad-spectrum herbicide that is extensively used worldwide, but its effects on the soil microbiome are inconsistent. To provide a sound scientific basis for herbicide re-review and registration decisions, we conducted a four-year (2013-2016) study in which we consecutively applied glyphosate to a wheat (Triticum aestivum L.)-field pea (Pisum sativum L.)-canola (Brassica napus L.)-wheat crop rotation at five sites in the Canadian prairies. The glyphosate rates were 0, 1, 2, 4 and 8 kg ae ha-1, applied pre-seeding and post-harvest every year. The wheat rhizosphere was sampled in the final year of the study and analysed for microbial biomass C (MBC), the composition and diversity of the microbiome, and activities of ß-glucosidase, N-acetyl-ß-glucosiminidase, acid phosphomonoesterase and arylsulphatase. Glyphosate did not affect MBC, the composition and diversity of prokaryotes and fungi, and the activities of three of the four enzymes measured in the wheat rhizosphere. The one effect of glyphosate was a wave-like response of N-acetyl-ß-glucosaminidase activity with increasing application rates. The experimental sites had much greater effects, driven by soil pH and organic C, on the soil microbiome composition and enzyme activities than glyphosate. Soil pH was positively correlated with the relative abundance of Acidobacteriota but negatively correlated with that of Actinobacteriota and Basidiomycota. Soil organic C was positively correlated with the relative abundances of Proteobacteriota and Verrucomicrobiota, but negatively correlated with the relative abundance of Crenachaeota. The activity of acid phosphomonoesterase declined with increasing relative abundance of Acidobacteriota, but increased with that of Actinobacteriota and Basidiomycota. The activity of N-acetyl-ß-glucosaminidase also increased with increasing relative abundance of Actinobacteriota but decreased with that of Mortierellomycota. ß-glucosidase activity also decreased with increasing relative abundance of Mortierellomycota. The core fungal species observed in at least 90% of the samples were Humicola nigrescens, Gibberella tricincta and Giberella fujikuroi. Therefore, this multi-site study on the Canadian prairies revealed no significant effects of 4-year applications of glyphosate applied at different rates on most soil microbial properties despite differences in the properties among sites. However, it is important to keep evaluating glyphosate effects on the soil microbiome and its functioning because it is the most widely used herbicide worldwide.

A-ring substituted 17ß-arylsulfonamides of 17ß-aminoestra-1,3,5(10)-trien-3-ol as highly potent reversible inhibitors of steroid sulfatase.

Steroid sulfatase (STS) catalyzes the hydrolysis of the sulfate ester group in biologically inactive sulfated steroids to give biologically active steroids. Inhibitors of STS are considered to be potential therapeutics for treating hormone-dependent cancers such as ER(+) breast cancer. A series of 4-substituted 17ß-arylsulfonamides of 17ß-aminoestra-1,3,5(10)-trien-3-ol were prepared and examined as STS inhibitors. The presence of a NO2 or Br at the 2-position of the A-ring resulted in a decrease in potency compared to their A-ring-unsubstituted counterparts. However the presence of a nitro group or fluorine atom at the 4-position of the A-ring resulted in an increase in potency and one of these compounds exhibited a Ki(app) value of 1 nM. Modeling studies provided insight into how these compounds interact with active site residues. The anti-proliferative activity of the 3'-Br, 3'-CF3, 4-NO2-3'-Br and 4-NO2-3'-CF3 derivatives were examined using the NCI 60-cell-line panel and found to have mean graph midpoint values of 1.9-3.4 µM.

17ß-Arylsulfonamides of 17ß-aminoestra-1,3,5(10)-trien-3-ol as highly potent inhibitors of steroid sulfatase.

Steroid sulfatase (STS) catalyzes the desulfation of biologically inactive sulfated steroids to yield biologically active desulfated steroids and is currently being examined as a target for therapeutic intervention for the treatment of breast and other steroid-dependent cancers. Here we report the synthesis of a series of 17ß-arylsulfonamides of 17ß-aminoestra-1,3,5(10)-trien-3-ol and their evaluation as inhibitors of STS. Some of these compounds are among the most potent reversible STS inhibitors reported to date. Introducing n-alkyl groups into the 4'-position of the 17ß-benzenesulfonamide derivative resulted in an increase in potency with the n-butyl derivative exhibiting the best potency with an IC(50) of 26 nM. A further increase in carbon units (to n-pentyl) resulted in a decrease in potency. Branching of the 4'-n-propyl group resulted in a decrease in potency while branching of the 4'-n-butyl group (to a tert-butyl group) resulted in a slight increase in potency (IC(50)=18 nM). Studies with 3'- and 4'-substituted substituted 17ß-benzenesulfonamides with small electron donating and electron withdrawing groups revealed the 3'-bromo and 3'-trifluoromethyl derivatives to be excellent inhibitors with IC(50)'s of 30 and 23 nM, respectively. The 17ß-2'-naphthalenesulfonamide was also an excellent inhibitor (IC(50)=20 nM) while the 17ß-4'-phenylbenzenesulfonamide derivative was the most potent inhibitor of all the compounds studied with an IC(50) of 9 nM.

Exocytosis of storage material in a lysosomal disorder.

Lysosomal exocytosis is a ubiquitously occurring process, which has a physiological role in repair of wounds of the plasma membrane. Lysosomal storage disorders are a group of more than 40 different diseases, which are characterized by intralysosomal storage of various substances. Metachromatic leukodystrophy is a lysosomal disease caused by the deficiency of arylsulfatase A, which results in the storage of the sphingolipid 3-O-sulfogalactosylceramide (sulfatide) in, e.g., oligodendrocytes and distal tubule kidney cells. Here we show that sulfatide storing cultured primary kidney cells of arylsulfatase A deficient mice can undergo calcium induced lysosomal exocytosis and that this results in the delivery of storage material to the culture medium. In metachromatic leukodystrophy extracellular sulfatide has been found in urine and cerebrospinal fluid. Lysosomal exocytosis may explain the presence of sulfatide in these body fluids.

Enzyme activities and arylsulfatase protein content of dust and the soil source: biochemical fingerprints?

Little is known about the potential of enzyme activities, which are sensitive to soil properties and management, for the characterization of dust properties. Enzyme activities may be among the dust properties key to identifying the soil source of dust. We generated dust (27 and 7 microm) under controlled laboratory conditions from agricultural soils (0-5 cm) with history of continuous cotton (Gossypium hirsutum L.) or cotton rotated with peanut (Arachis hypogaea L.), sorghum [Sorghum bicolor (L.) Moench], rye (Secale cereale L.), or wheat (Triticum aestivum L.) under different water management (irrigated or dryland) and tillage (conservation or conventional) systems. The 27- and 7-microm dust samples showed activities of beta-glucosidase, alkaline phosphatase, and arylsulfatase, which are related to cellulose degradation and phosphorus and sulfur mineralization in soil, respectively. Dust samples generated from a loam and sandy clay loam showed higher enzyme activities compared with dust samples from a fine sandy loam. Enzyme activities of dust samples were significantly correlated to the activities of the soil source with r > 0.74 (P < 0.01). The arylsulfatase proteins contents of the soils (0.04-0.65 mg protein kg(-1) soil) were lower than values reported for soils from other regions, but still dust contained arylsulfatase protein. The three enzyme activities studied, as a group, separated the dust samples due to the crop rotation or tillage practice history of the soil source. The results indicated that the enzyme activities of dust will aid in providing better characterization of dust properties and expanding our understanding of soil and air quality impacts related to wind erosion.

Biodegradation of linear alkylbenzene sulfonates in sulfate-leached soil mesocosms.

Aromatic sulfonates (R-SO(3)(-)) can be used as sulfur sources by sulfate-starved bacteria in laboratory cultures and the corresponding phenols are excreted from the cells. The present study was conducted to demonstrate whether such desulfonation reactions also occur in sulfate-leached agricultural soil, where desulfonation of organic sulfur compounds may have agronomic importance as a S source for plants. Xenobiotic linear alkylbenzene sulfonates (LAS) were added to nominal concentrations of 0, 10 and 100 mgkg(-1) dry weight in a sandy soil that was depleted in sulfate by leaching the soil with water (sulfate depletion, approximately 75%). The soil was incubated at 20 degrees C in duplicate 3-dm(3) mesocosms for 8 weeks. Primary degradation of LAS was rapid with half-lives of 1-4 days. Sulfophenylcarboxylates were identified and quantified as intermediates, whereas linear alkylphenols (the expected primary desulfonation products) were not detected by high-pressure liquid chromatography coupled with both fluorescence and electrospray ionization-mass spectrometry. Thus, LAS was used by the bacteria as a source of energy and carbon, rather than as a source of sulfur. Measurements of soil pH, fluorescein diacetate (FDA) hydrolysis and arylsulfatase activity showed that stable microbial conditions prevailed in the soil mesocosms. FDA hydrolysis (a measure of total microbial activity) was transiently inhibited at the highest LAS concentrations. Arylsulfatase activity (i.e., hydrolysis of aromatic sulfate esters) was not significantly affected by the soil incubation, although arylsulfatases may be upregulated in sulfate-starved bacteria. However, an increased production of arylsulfatase may be difficult to detect due to the background of extracellular arylsulfatases stabilised in the soil. Therefore, the present data does not exclude a regulatory response to sulfate depletion by the soil microorganisms. However, the importance of desulfonation reactions in natural environments still needs to be demonstrated.

Urinary metabolites of daidzin orally administered in rats.

In a study on the metabolism of flavonoids, the isoflavone glycoside daidzin was orally administered to rats. Urine samples were collected and treated with beta-glucuronidase and arylsulfatase. Aglycone daidzein (M3) and other three metabolites, 3',4',7-trihydroxyisoflavone (M1), 4',7-dihydroxyisoflavanone (M2) and 4',7-dihydroxyisoflavan (M4) were isolated from the urine following treatment with enzymes. The structures of M1, M2 and M4 were determined on the basis of chemical and spectral data.

Chemical characterization and regulation of endogenous morphine and codeine in the rat.

Data on the tissue distribution of morphine and codeine in rat are presented. The concentration of these two opiate alkaloids seems to be distributed uniformly in the cortex, midbrain, pons/medulla and cerebellum. The spinal cord and the adrenal gland have high levels of morphine and codeine and the adrenal has more codeine than morphine. The major fraction of the alkaloids reside in a synaptosomal fraction and are present in tissues as the sulfate conjugate. The levels of morphine in the spinal cord and the urinary excretion of morphine are elevated in the arthritic rat model. We used extracted alkaloid samples from arthritic rats spinal cord for analysis by mass spectrometry and found molecular ions identical with morphine and codeine. The results are discussed in the light of possible physiological roles of endogenous morphine and codeine.

3,4-Dichlorobenzyloxyacetic acid is extensively metabolized to a taurine conjugate in rats.

The metabolism of the antisickling agent 3,4-dichlorobenzyloxyacetic acid (3,4-DCBAA) was examined after ip administration to rats. Within 5 days after administration of radiolabeled 3,4-DCBAA, 77.4 +/- 4.6% of the dose was recovered in the urine and only 3.2 +/- 0.5% was recovered in the feces. Metabolites in the urine were isolated and characterized by HPLC, electron impact MS, and LC/MS, and their identities were confirmed by comparing their spectra with those of synthetic standards. Quantitation of these urinary metabolites revealed that the majority of the radioactive dose was excreted as a taurine conjugate (60.1 +/- 4.4%), while lesser amounts were excreted as 3,4-dichlorohippurate, unchanged 3,4-DCBAA, the glycine conjugate of 3,4-DCBAA, and a polar unknown which is believed to be glycolic acid. A pathway involving an initial O-dealkylation at the benzyl carbon of 3,4-DCBAA and proceeding through the glycine conjugation of 3,4-dichlorobenzoic acid has been proposed to explain the formation of 3,4-dichlorohippurate and the polar unknown. The extensive conjugation of 3,4-DCBAA with taurine is an unprecedented observation in rats, which usually utilize glycine for amino acid conjugation reactions. Further studies with 3,4-DCBAA may provide insight into the enzymatic mechanisms of taurine conjugation, which are not well defined at this time.

Enzymatic study to characterize the slow reacting substance of anaphylaxis (SRS-A) and leukotrienes.

Slow reacting substance of anaphylaxis (SRS-A) has been shown to be one of the major mediators in hypersensitive reactions and to be composed of leukotriene (LT) C4, LTD4 and LTE4. In the present study, we examined the properties of SRS-A released from sensitized guinea pig lungs by antigen and SRS released from rat peritoneal exudate cells and from human leucocytes by ionophore A23187 (0.5 and 0.2 microgram/ml, respectively). By the incubation with SRS-A, SRS and LTs with arylsulfatase (type V) in pH 5.7 buffered solution at 37 degrees C for 30 min, SRS-A and LTD4 were greatly inactivated and rat SRS was slightly inactivated, but human SRS and LTC4 were not inactivated at all. The same results were obtained when aminopeptidase was used in place of arylsulfatase. Moreover, when SRS-A, LTC4 and LTD4 were incubated with 0.02 mg/ml of gamma-glutamyltranspeptidase (gamma-GTP) pH 8.0 buffered solution at 37 degrees C for 30 min, the activities of SRS-A and LTD4 were slightly decreased, but those of SRS and LTC4 were obviously potentiated. On the other hand, incubation with a large amount of gamma-GTP (0.2 mg/ml) a dose at which this enzyme preparation showed clear aminopeptidase activity, SRS-A, SRS, LTC4 and LTD4 were obviously inactivated. In addition, we found a peak of LTD4 in guinea pig SRS-A, that of LTC4 in human SRS, and that of LTC4 in rat SRS on high performance liquid chromatograms. From these results, we demonstrated that guinea pig lung SRS-A is mainly composed of LTD4, human leukocyte SRS is mainly LTC4, and rat peritoneal SRS is composed of both LTC4 and LTD4. The inactivation of LTD4 and SRS-A by arylsulfatase may be due to aminopeptidase contamination in the enzyme preparation.

Role of sulfatide on phosphoenzyme formation and ouabain binding of the (Na+ + K+)ATPase.

A microsomal fraction rich in (Na+ + K+)ATPase activity has been isolated from the outer medulla of pig kidney. The ability of this preparation to form phosphoenzyme on incubation with [gamma-32P]ATP and to bind [3H]ouabain was studied when its sulfatide was hydrolyzed by arylsulfatase treatment. The K+-dependent hydrolysis of the Na+-dependent phosphorylated intermediate as well as the ouabain binding were inactivated in direct relation to the breakdown of sulfatide. Both characteristics of the (Na+ + K+)ATPase preparation, lost by arylsulfatase treatment, were partially restored by the sole addition of sulfatide. These experiments indicate that sulfatide may play a role in sodium ion transport either in the conformational transition of the K+-insensitive phosphointermediate, E1P, to the K+-sensitive intermediate, E2P, or in the configuration of the high-affinity binding site for K+ of the E2P form. In addition, this glycolipid may have a specific role in the proteolipidic subunit that binds ouabain.

[Characterization of slow reacting substance of anaphylaxis in asthmatic sputum].

Sputum from asthmatics contained a mediator similar to slow reacting substance of anaphylaxis (SRS-A), capable of inducing contraction of guinea pig ileum. This mediator possessed the major characteristics of SRS-A, including stability in both neutral and alkaline solutions, lability in boiling acidic solution, destruction by arylsulfatase, inhibition by FPL 55712 and resistance to diphenhy dramine . Thus, we proved that the "SRS-A like" mediator was in fact SRS-A. The activity of histamine in these patients' sputa could be inhibited only by diphenhydramine, but could not be altered by any of the other treatments noted above.

Functional opiate receptor in mouse vas deferens: evidence for a complex interaction.

Treatment of the isolated mouse was deferens with the enzyme arylsulfatase (E.C. 3.1.6.1) had an effect on the ability of this tissue to respond to various opiates. It increased the IC50 values and slopes of their dose-response curve for enkephalins and their analogs, and shifted to the right the curves for FK33824, levorphanol and normorphine. There was no effect on the action of etorphine, beta-endorphin or dynorphin. With morphine there was a biphasic effect, IC50 values increasing at low enzyme concentrations and decreasing at high enzyme concentrations. A further comparison of arylsulfatase effects on morphine and on D-Ala-2-D-Leu5-enkephalin indicated that the morphine effect, unlike the D-Ala-2-D-Leu5-enkephalin effect, could not be reversed by washing and that morphine, unlike D-Ala2-D-Leu5-enkephalin, became much less sensitive to naloxone antagonism. The observed modifications in the shape of the dose-response curves indicate that the effect of the opiates in the mouse vas deferens is more complex than that expected through the occupation of a simple receptor. There is either more than one type of functional receptor for each agonist or only one receptor, which can interact with every drug in different ways; this complexity is discussed in terms of various possibilities, including fractional occupancy, positive cooperativity and multiple sites.

Differential modification of opiate receptor activity by arylsulfatase treatment.

Treatment with the enzyme arylsulfatase in vivo selectively attenuated the effect of analgesia induced by morphine, beta-endorphin or ethylketocyclazocine but not that induced by Sandoz FK33824 or D-ala2-D-leu5-enkephalin. The effect on morphine analgesia was indicated both by an increased morphine ED50 in the presence of a fixed dose of naloxone and by a decreased naloxone ED50 in the presence of a fixed dose of morphine. Arylsulfatase treatment in vivo also selectively affected in vitro ligand binding; Bmax values of the low affinity binding site of dihydromorphine, naloxone, D-ala2-D-leu5-enkephalin, D-ala2-met5-enkephalinamide and ethylketocyclazocine were decreased significantly while the Bmax values of the high affinity sites as well as the KD values of both the high and low affinity sites were affected little or not at all. The data suggest that the change induced by the enzyme may have been due to the alteration of certain constituents of the low affinity opiate binding site.

Sulfatide role in the sodium pump.

Sodium efflux was studied in 22Na-loaded red blood cells in the presence of arylsulfatase, an enzyme that specifically hydrolyzes sulfatide. Sodium efflux was inhibited in proportion to the amount of arylsulfatase present. Maximum inhibition was almost as high as the efflux obtained in medium with K+ absent. At maximum inhibition 83.2% of the sulfatide content of the fragmented red blood cell membranes was hydrolyzed and ouabain-sensitive (Na+ + K+)-ATPase activity was inhibited by 100%. Sodium efflux, sulfatide content, and (Na+ + K+)-ATPase activity were unaffected with arylsulfatase in the presence of a high concentration of sulfatide. These results indicate that sulfatide plays a specific role in sodium and potassium ion transport. They also suggest that most sulfatide is localized externally in the red blood cell membrane.

Release of slow reacting substance (SRS) from rat basophilic leukemia (RBL-1) cells.

When rat basophilic leukemia (RBL-1) cells were exposed to the ionophore A23187, a substance was released that produced a prolonged contraction of guinea pig ileum resembling that seen with slow reacting substances (SRSs) from various sources. The response was temperature, dose, and the time dependent with no activity being demonstrated in unstimulated cells. Several lines of evidence indicated that the RBL-1 product was markedly similar or identical to SRSs obtained from non-neoplastic tissues: 1) appropriate behavior in seven different chromatographic systems, 2) an appropriate profile of activity on various smooth muscle preparations, 3) an ability of low concentrations of the selective SRS inhibitor FPL 55712 to block the guinea pig ileal response, 4) failure of chymotrypsin to destroy activity, 5) loss of the activity after incubation with arylsulfatase, and 6) an ability to release activity from cells preincubated with indomethacin. Since RBL-1 cells can be grown in considerable guantity and under optimal conditions an average of 1500 SRS units/10(7) cells can be obtained, these cells should be useful as a biosynthetic source in further attempts to purify and characterize the SRS molecule.

Tissue inactivation of slow reacting substance of anaphylaxis.

The release of slow reacting substance of anaphylaxis (SRS-A) from sensitized guinea-pig lung challenged with antigen was followed by a fall in the activity of this mediator in the diffusate when the incubations were continued for 3 h. The inactivating principle was also present in normal lung in addition to other normal guinea-pig tissues such as the liver, kidney, spleen, ileum and skin. No acitivity was found in muscle. Evidence is provided that some of this SRS-A-inactivating activity was due to tissue arylsulphatases. These were measured by hydrolysis of p-nitrophenyl sulphate (p-NPS) and p-nitrocatechol sulphate (p-NCS), which reflect activities of arylsulphatase II A and II B respectively. Hydrolytic activity for p-NCS was present in all tissues with SRS-A-inactivating properties, whereas only lung, liver and skin tissue hydrolysed p-NCS and p-NPS. Following passage of a cell-free lung homogenate through a column of Sephadex G-200 the p-NCS hydrolysing and SRS-Z-inactivating activities eluted together, with molecules having a molecular size of approximately 150,000 Daltons, p-NPS hydrolysing activity being destroyed during the preparation of the homogenate. The release of arylsulphatase from sensitized tissue was not dependent on the presence of specific antigen. These experiments suggest that inactivation of SRS-A is related to tissue arylsulphatase and that these enzymes may play a role in the expression of the effective levels of this mediator within the tissues.