Metabolism of Sulfur Compounds (Sulfate Metabolism)

Gregory, John D.; Robbins, Phillips W.

doi:10.1146/annurev.bi.29.070160.002023

Cited by 93 publications

(44 citation statements)

References 62 publications

(77 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The nutrient solution con- Wilson and Bandurski showed that a stable adenylic acid-anion anhydride was not formed with molybdate. This overcomes the unfavorable equilibrium of the reaction and allows it to proceed at a measurable rate (6).…”

Section: Methodsmentioning

confidence: 99%

ATP Sulfurylase Activity in the Soybean [Glycine max (L.) Merr.]

Adams

Johnson

1968

Plant Physiol.

View full text Add to dashboard Cite

Abstract. ATP sulfurylase activity was assayed in soybean leaf extracts. A simple, rapid assay system using molybdate as an analogue of sulfate was developed. The assay was coupled to inorganic pyrophosphatase. The high pyrophosphatase level in soybean leaf extracts obviated the necessity of adding this enzyme to the assay system. ATP sulfurylase has a pH maximum above 7.5, uses molybdate and ATP as substrates, and requires magnesium ions for activity.ATP sulfurylase (ATP: sulfate adenylyltransferase E. C. 2.7.7.4) mediates the reaction between ATP and sulfate to yield APS.3 The discovery of this enzyme and its distribution has been described by Gregory and Robbins (6).There is a paucity of information on the biochemistry and physiology of sulfur metabolism in higher plants in general and of ATP sulfurylase in particular. The only published work is by Asahi (1). He reported the level of ATP sulfurylase activity in a spinach chloroplast preparation, but pursued the matter no further. Also, there has been little work on sulfur metabolism of the soybean since the experiments of Eaton (4).The objectives of the experiments reported here were to first develop an improved assay for ATP sulfurylase in the soybean and then to use this assay to investigate the biochemical properties of the enzyme.The assay described is simple and rapid and, unlike that of Panikkar and Bachhawat (7), requires no difficultly obtainable substrates. Materials and MethodsAll the experiments were conducted using Harosoy 63 soybean leaves as a source of plant material. Seeds were germinated in sand and transferred to nutrient solution in a greenhouse at the unifoliate stage. The nutrient culture apparatus has been previously described (3). The nutrient solution con-

show abstract

Section: Methodsmentioning

confidence: 99%

ATP Sulfurylase Activity in the Soybean [Glycine max (L.) Merr.]

Adams

Johnson

1968

Plant Physiol.

View full text Add to dashboard Cite

show abstract

“…The transfer of a sulphonate group (SO" − $ ) from a donor to an acceptor molecule is a fundamental process in the biotransformation of a host of endogenous compounds, as well as drugs and xenobiotics [1]. In order for sulphonation to occur, however, inorganic sulphate must be activated to a high-energy form prior to being transferred to an acceptor molecule [2,3]. The activated form of sulphate and universal sulphonate donor molecule is 3h-phosphoadenosine 5h-phosphosulphate (PAPS).…”

Section: Introductionmentioning

confidence: 99%

Characterization and expression of human bifunctional 3′-phosphoadenosine 5′-phosphosulphate synthase isoforms

Fuda

Shimizu

Lee

et al. 2002

Biochemical Journal

View full text Add to dashboard Cite

Sulphonation, a fundamental process essential for normal growth and development, requires the sulphonate donor molecule 3h-phosphoadenosine 5h-phosphosulphate (PAPS), which is produced from ATP and inorganic sulphate by the bifunctional enzyme PAPS synthase. In humans, two genes encode isoenzymes that are 77 % identical at the amino acid level, and alternative splicing creates two subtypes of PAPS synthase 2. The question as to whether distinctions in amino acid composition are reflected in differences in activity has been examined. The specific activity of the PAPS synthase 2 subtypes is 10-to 15-fold higher than that for PAPS synthase 1. The greater catalytic efficiency of the PAPS synthase 2 subtypes is demonstrated further by the 3-to 6-fold higher k cat \K m ratios for ATP and inorganic sulphate as compared with the ratios for PAPS synthase 1. In humans, PAPS synthase 1 is expressed ubiquitously, and is the dominant isoform in most tissues, whereas expression of the PAPS synthase 2

show abstract

“…In some microorganisms, an enzyme APS3-kinase (EC 2.7.1.25) further activates APS to PAPS (8,15 Most studies of sulfate reduction in higher plants have been limited to leaves. However, Ellis (7) and Balharry and Nicholas (4) demonstrated substantial ATP-sulfurylase activities in tomato roots and root tips of oat seedlings, respectively.…”

mentioning

confidence: 99%

“…In some microorganisms, an enzyme APS3-kinase (EC 2.7.1.25) further activates APS to PAPS (8,15). In studies with the green alga (Chlorella pyrenoidosa), Schiff and his collaborators (9) identified PAPS 'Abbreviations: APS: adenosine-5'-phosphosulfate; PAPS: adenosine-3'-phosphate-5'-phosphosulfate; DEAE: diethylaminoethyl. fate in higher plants have been few (19).…”

mentioning

confidence: 99%

Adenosine 5′-Triphosphate-Sulfurylase in Corn Roots and Its Partial Purification

Onajobi

Cole²,

Ross³

1973

Plant Physiol.

View full text Add to dashboard Cite

ATP-sulfurylase (ATP-sulfate adenyltransferase, EC 2.7.7.4) was found in nonparticulate fractions of both roots and leaves of Zea mays L. seedlings using two detection methods. Addition of exogenous pyrophosphatase was essential for maximum rates of conversion of 3SO2-to labeled adenosine phosphosulfate in unpurified root extracts, but not in unpurified leaf extracts. In the presence of exogenous pyrophosphatase, the enzyme from roots exhibited specific activities as high as those obtained with the leaf enzyme. The root enzyme was purified 33-fold by centrifugation and column chromatography procedures. Its molecular weight obtained by Sephadex gel filtration was about 42,000. Its Kit for pyrophosphate was 7 AM, while for adenosine phosphosulfate, the Km was 1.35 uM.None of the enzyme fractions studied converted adenosine phosphosulfate into detectable amounts of 3'-phosphoadenosine-5'-phosphosulfate. ATP-sulfurylase was also found in roots of corn seedlings grown aseptically. The data suggest that at least the first reaction in sulfate reduction might proceed as effectively in roots as in shoots.The mechanisms of sulfate reduction in microorganisms have been studied extensively (10,14,15,17,(23)(24)(25). These studies showed that the first step in the metabolism of sulfate is the activation of sulfate by ATP-sulfurylase (EC 2.7.7.4) according to the following: ATP + SO42= APS + PPiIn some microorganisms, an enzyme APS3-kinase (EC 2.7.1.25) further activates APS to PAPS (8,15 Most studies of sulfate reduction in higher plants have been limited to leaves. However, Ellis (7) and Balharry and Nicholas (4) demonstrated substantial ATP-sulfurylase activities in tomato roots and root tips of oat seedlings, respectively. We have discovered that excised corn roots show as much ATP-sulfurylase activity as corn leaves. This paper presents a method for partial purification and some properties of the ATP-sulfurylase of corn roots. MATERIALS AND METHODSRadioactive materials (H2I'SO, and H332P04) were obtained The roots of these seedlings were freed of agar and used for the preparation of sulfurylase enzyme under sterile conditions.

show abstract

Metabolism of Sulfur Compounds (Sulfate Metabolism)

Cited by 93 publications

References 62 publications

ATP Sulfurylase Activity in the Soybean [Glycine max (L.) Merr.]

ATP Sulfurylase Activity in the Soybean [Glycine max (L.) Merr.]

Characterization and expression of human bifunctional 3′-phosphoadenosine 5′-phosphosulphate synthase isoforms

Adenosine 5′-Triphosphate-Sulfurylase in Corn Roots and Its Partial Purification

Contact Info

Product

Resources

About