| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J. Biol. Chem., Vol. 275, Issue 31, 23769-23773, August 4, 2000
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
§,
From the Laboratory of Biochemistry, NHLBI, National
Institutes of Health, Bethesda, Maryland 20892 and the ¶ Institute
for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
Received for publication, February 4, 2000, and in revised form, May 16, 2000
 |
ABSTRACT |
|---|
 TOP
 ABSTRACT
 INTRODUCTION
EXPERIMENTAL PROCEDURES
RESULTS AND DISCUSSION
REFERENCES
|
|---|
Selenophosphate synthetase (SPS), the
selD gene product from Escherichia coli,
catalyzes the biosynthesis of monoselenophosphate, AMP, and
orthophosphate in a 1:1:1 ratio from selenide and ATP. Kinetic
characterization revealed the Km value for selenide approached levels that are toxic to the cell. Our previous
demonstration that a Se0-generating system consisting of
L-selenocysteine and the Azotobacter vinelandii
NifS protein can replace selenide for selenophosphate biosynthesis
in vitro suggested a mechanism whereby cells can overcome
selenide toxicity. Recently, three E. coli NifS-like proteins, CsdB, CSD, and IscS, have been overexpressed and
characterized. All three enzymes act on selenocysteine and cysteine to
produce Se0 and S0, respectively. In the
present study, we demonstrate the ability of each E. coli
NifS-like protein to function as a selenium delivery protein for the
in vitro biosynthesis of selenophosphate by E. coli wild-type SPS. Significantly, the SPS (C17S) mutant,
which is inactive in the standard in vitro assay with
selenide as substrate, was found to exhibit detectable activity in the
presence of CsdB, CSD, or IscS and L-selenocysteine. Taken
together the ability of the NifS-like proteins to generate a selenium
substrate for SPS and the activation of the SPS (C17S) mutant suggest a
selenium delivery function for the proteins in
vivo.
The highly reactive, reduced selenium compound monoselenophosphate
is required for the insertion of selenium into
selenium-dependent enzymes (1) and seleno-tRNAs (2). The
selD gene product from Escherichia coli catalyzes
the synthesis of monoselenophosphate, AMP, and orthophosphate in a
1:1:1 ratio from selenide and ATP (Reaction 1).
INTRODUCTION
TOP
ABSTRACT
INTRODUCTION
EXPERIMENTAL PROCEDURES
RESULTS AND DISCUSSION
REFERENCES
Selenophosphate synthetase
(SPS)1 from E. coli (3) and the closely related enzyme from Haemophilus
influenzae (4) have been characterized. Both enzymes are active in
the presence of high levels of free selenide (1-5 mM) and
dithiothreitol (8-10 mM) that are included in the
in vitro assay system employed routinely. Under these
conditions, the apparent Km values for ATP and
selenide are 1 mM and 20 µM, respectively.
Although the reactions are carried out under argon, any traces of
contaminating oxygen tend to reduce the effective concentration of
selenide. The standard use of high selenide levels in vitro
is a partial solution of this problem.
The Km value determined for selenide in the in vitro system is far above the optimal concentration (0.1-1 µM) of selenium needed for the growth of various bacterial species and cultured mammalian cells. In fact, levels above 10 µM are toxic for many bacterial species. The fact that the high reactivity and thus the toxicity of selenide in biological systems is even greater than that of sulfide is apparent from the greater extent of ionization at physiological pH of H2Se with a pK1 = 3.89 as compared with that of H2S with a pK1 = 7.5. Rate acceleration by ionized selenols of disulfide reduction and disruption of protein structures or destabilization of coordinated metal ions from metallothionines (5) can occur if selenide concentrations are not maintained at low and optimal levels. Potential candidates for control of selenium levels are the specific L-selenocysteine-lyase enzymes that decompose selenocysteine to elemental selenium (Se0) and alanine (6, 7) and a closely related enzyme D-selenocystine-lyase (8). The attractive possibility that these lyases also may serve normally to deliver Se0 to SPS was suggested by previous studies in which it was shown that L-selenocysteine and the Azotobacter vinelandii NifS protein effectively replaced the high level of free selenide in the in vitro SPS assay (9). In fact, even though the normal substrate for A. vinelandii NifS is cysteine (10, 11), the extent of utilization of selenocysteine in vitro was sufficient to promote a higher rate of selenophosphate formation by SPS than was observed with free selenide alone.
The A. vinelandii NifS protein and the selenocysteine-lyases are pyridoxal 5'-phosphate-dependent enzymes that catalyze the elimination of sulfur from L-cysteine and selenium from L-selenocysteine (10, 11). Because in vivo concentrations of sulfur-containing compounds are a thousand-fold or more greater than their selenium analogs, proteins such as NifS presumably bind and metabolize L-cysteine preferentially. Thus, lyase proteins that are highly specific for L-selenocysteine as substrate may function as the actual selenium delivery proteins in vivo. In E. coli three NifS-like proteins were identified recently (12). All three proteins resemble A. vinelandii NifS in amino acid sequences and catalytic properties. Sequence alignments also revealed similarities between the N-terminal region amino acid sequence of the pig liver selenocysteine-lyase (6). Characterization of the three E. coli NifS-like proteins CsdB, CSD, and IscS revealed considerable differences in the degree of discrimination between L-cysteine and L-selenocysteine as substrates (12). The CsdB protein, although not entirely specific for the seleno-amino acid, substrate was 290 times more active on L-selenocysteine than on L-cysteine. This protein thus appears to be the E. coli counterpart of the mammalian selenocysteine-lyase.
In an attempt to identify residues that are essential for catalysis in
the SPS enzyme, mutagenesis experiments have been performed (13, 14).
Certain amino acids in a glycine-rich potential ATP-binding site in the
N-terminal region of the protein were selected as targets. Mutagenesis
of cysteine 17, located in the potential ATP-binding site, to serine
resulted in the complete loss of detectable SPS activity in both the
in vitro selenide-dependent assay and the
in vivo complementation of a selD lesion in
E. coli strain MBO8 (13). The inability to detect SPS
catalytic activity of the cysteine 17 mutant enzyme and the failure of
this mutated enzyme to catalyze a positional isotope exchange reaction
between the 
-phosphoryl group and the 
-phosphoryl group of
ATP2 supported a catalytic
role for cysteine 17. However, a catalytic role was contradicted by the
finding that substitution of selenocysteine for cysteine at position
17, which occurs normally in H. influenzae SPS, fails to
elicit an increase in catalytic activity (4). In the present work, we
report the ability of the CsdB, CSD, and IscS proteins to function both
in vitro and in vivo as selenium delivery
proteins to the E. coli wild-type SPS and also to SPS (C17S) mutant.
| |
EXPERIMENTAL PROCEDURES |
|---|
|
TOP
ABSTRACT
INTRODUCTION
EXPERIMENTAL PROCEDURES
RESULTS AND DISCUSSION
REFERENCES
|
|---|
Materials
L-Selenocystine was synthesized (15) and converted to L-selenocysteine as reported (6). [8-14C]ATP was purchased from ICN Biomedical Research Products, Costa Mesa, CA. [75Se]Selenite was purchased from The University of Missouri Research Reactor Facility, Columbia, MO. The lyase proteins CsdB, CSD, and IscS were purified as described by Mihara et al. (12). SPS was purified by the procedure of Veres et al. (3).
Methods
Complementation of the selD Mutant MBO8-- E. coli strain MB08 (16, 17) transformed with plasmids containing either the SPS gene or the SPS (C17S) mutant gene was grown anaerobically at 37 °C overnight in Luria broth containing 0.5% glucose. Cultures were observed after 24-48 h for the production of H2, a product of an active formate dehydrogenase (FDHH)-hydrogenase H complex (also known as formate hydrogen-lyase) (18). Synthesis of the selenocysteine-containing FDHH depends on the availability of selenophosphate.
In parallel experiments, MBO8 cultures containing both plasmids were streaked out on Luria medium plus glucose agar plates and incubated anaerobically for 48 h at 37 °C. After growth, all individual colonies were colorless. The plates were then overlaid with agar containing benzyl viologen, an electron acceptor for active FDHH that turns blue when reduced. Thus, any colonies appearing blue in color provide a test for the presence of FDHH (19).
[75Se]Selenocysteine-labeled
FDHH--
Single colonies of MBO8, MBO8/SPS, and MBO8/SPS
(C17S) were grown anaerobically in Luria broth + 20 µCi
75SeO32
at 37 °C for
24 h. Following growth, cells were harvested, resuspended in 100 mM potassium phosphate buffer, pH 7.2, and sonicated.
Supernatants were analyzed for the presence of the selenocysteine
containing FDHH by SDS-polyacrylamide gel electrophoresis
and PhosphorImager detection of radioactivity.
Enzyme Assays-- All assays were performed anaerobically three to six times and averaged for each reported value. The coupled SPS-lyase assay reaction mixtures contained 50 mM Tricine·KOH, pH 8.0, 8 mM MgCl2, 20 mM KCl, 50 mM dithiothreitol, 200 µM pyridoxal 5'-phosphate, 2 mM ATP, 10 mM L-selenocysteine, 10 µM SPS, 0.2 µCi [8-14C] ATP, and the indicated concentration of added lyase. Reaction mixtures were incubated at 37 °C for 30 min, terminated by the addition of 1.2 N HClO4, and neutralized with KOH. A standard assay, in which selenide replaced L-selenocysteine and lyase protein, was performed at the same time. The nucleotides in the supernatant solutions were separated by chromatography on cellulose-polyethyleneimine thin layer sheets developed in 1.0 M formic acid and 0.5 M LiCl. Nucleotide spots detected by UV quenching were cut out, and radioactivity was measured by liquid scintillation spectroscopy.
The selenocysteine-lyase activity of each protein was measured in the
absence of selenophosphate synthetase by quantitation of liberated
H2Se after reaction with lead acetate as described previously (6). Reaction mixtures contained 50 mM
Tricine·KOH, pH 8.0, 8 mM MgCl2, 20 mM KCl, 50 mM dithiothreitol, 200 µM pyridoxal 5'-phosphate, 10 mM
L-selenocysteine, and 2.5 µM lyase. Reaction mixtures were incubated at 37 °C for the indicated amounts of time,
and reactions were quenched by the addition of lead acetate. The amount
of H2Se produced was quantitated using a molar turbidity coefficient of colloidal PbSe at 400 nm of 1.18 × 104
cm1
M1.
The competition experiments with the CsdB (R379A) mutant were performed
as described above for the coupled assay. A total of five assays was
performed, each in the presence of a different concentration of CsdB
(R379A) (0.25, 0.5, 1, 5, and 10 µM). The assays
performed with SPS (C17S) mutant were performed as described above.
| |
RESULTS AND DISCUSSION |
|---|
|
TOP
ABSTRACT
INTRODUCTION
EXPERIMENTAL PROCEDURES
RESULTS AND DISCUSSION
REFERENCES
|
|---|
Selenophosphate Synthetase- and Lyase-coupled Assays--
As
previously reported, the high levels of free selenide that are used
routinely for SPS can be replaced by the A. vinelandii NifS
protein and L-selenocysteine in the in vitro SPS
assay (9). Even though the normal substrate for NifS is cysteine, the
ability to act also on the selenium analog makes it an effective
selenium donor in vitro. In this coupled assay, an increase
in selenophosphate formation was observed, indicating that
Se0 generated by the NifS protein is a more effective
substrate than free selenide (9). Recently, three E. coli
genes encoding the NifS-like proteins CsdB, CSD, and IscS were cloned,
and the gene products were characterized (12). All three proteins
exhibit lyase activity on L-cysteine and
L-selenocysteine as substrates and produce sulfane sulfur,
S0, or Se0 respectively. One of the proteins,
CsdB, utilizes selenocysteine more effectively than cysteine,
indicating a more specific role for Se0 generation. To test
the relative abilities of the three NifS-like proteins from E. coli to provide Se0 to SPS, assays were performed with
L-selenocysteine and CsdB, CSD, or IscS in place of high
levels of free selenide. SPS catalytic activity was supported in the
presence of each NifS-like protein (Fig.
1A). The determined activity
of SPS was directly related to the concentration of lyase used in each
assay. When lyase concentrations were increased above 0.025 µM, the amount of AMP generated by SPS was slightly
higher than AMP formed in assays using 1.5 mM free selenide
as substrate (data not shown). However, at lyase concentrations above
0.05 µM, the amount of selenide generated was much higher
(Fig. 1B) as compared with the amount of AMP generated by
SPS. (In the absence of an acceptor (SPS) and in free solution the
product of the lyase reaction is referred to as selenide.) The
inability to detect increased SPS activity in the presence of higher
concentrations of lyase indicates SPS is saturated with selenium. SPS
may have an inherently low catalytic rate because of a possible
rate-limiting step in the reaction mechanism. The rate-limiting step
may occur after selenium binding and could include bound ADP hydrolysis
(20), product release (AMP) or an enzyme conformational change.
|
In Vivo Selenophosphate Synthetase Assay-- An in vivo test to detect activity of the formate hydrogen-lyase complex in E. coli depends on the evolution of gas (H2) from formate generated during anaerobic growth on glucose (18). This test was later extended to detect in vivo activity of the selD gene (13, 14). The selD gene product, SPS, forms the reactive selenium donor compound, selenophosphate, which is required for the production of selenocysteyl-tRNASec (21). The synthesis of an active selenocysteine containing formate dehydrogenase depends on the availability of selenocysteyl-tRNASec. A more sensitive in vivo test, devised for the detection of redox-active enzymes such as formate dehydrogenase, involves the ability of the enzyme to reduce benzyl viologen to a blue color when agar containing the dye was overlaid on bacterial colonies grown anaerobically on glucose agar plates. E. coli MBO8, a selD mutant strain, cannot make selenophosphate and lacks an active selenocysteine containing formate dehydrogenase. Therefore, MBO8 fails to produce H2 when grown in glucose media (16, 17) and is unable to reduce benzyl viologen, resulting in colonies that do not turn blue. Introduction of a plasmid bearing a wild-type selD gene into MBO8 complements the selD lesion and allows the synthesis of an active selenocysteine containing formate dehydrogenase that can be detected in both in vivo assays (Data not shown) (22).
The SPS (C17S) mutation failed to complement the selD lesion in MBO8 as judged by lack of visible H2 production from glucose during anaerobic growth (13, 14). The purified mutant enzyme was also unable to catalyze the formation of selenophosphate from 1.5 mM selenide and ATP in the usual in vitro assay (13, 14). To re-evaluate the activity of the SPS (C17S) mutant, MBO8 cells were transformed with a plasmid bearing the mutant gene. In the benzyl viologen overlay assay the SPS (C17S) mutant gene was able to complement the selD lesion, and transformed MBO8 colonies turned blue in color (data not shown). Although reduction of benzyl viologen is a more sensitive test for FDHH activity than production of H2 gas in glucose media, the extent of blue color development is more qualitative than quantitative. Nevertheless, the benzyl viologen assay is a rapid and selective assay for determining formate dehydrogenase activity (19). MBO8 colonies bearing either the wild-type SPS or the mutant SPS (C17S) gene turned blue in the assay.
To compare the in vivo activities of wild-type SPS and SPS
(C17S), MBO8 cells containing plasmids bearing either gene were grown
anaerobically in the presence of
75SeO32. After growth,
cell extracts were prepared and examined for the presence of
[75Se]selenocysteine containing FDHH (Fig.
2). MBO8 cells alone are unable to
incorporate selenocysteine into FDHH. However, the
selD lesion in MBO8 cells can be complemented either by a
plasmid bearing the SPS gene or a plasmid bearing the SPS (C17S) mutant
gene, thus restoring incorporation of selenocysteine into
FDHH. Quantitation of the amount of radioactivity in
FDHH in response to the two gene products (Fig. 2) revealed
that the level of selenophosphate synthesis by the SPS (C17S) gene
product was sufficient to allow incorporation of 44% as much
75Se into FDHH as observed with the wild-type
SPS. The fact that the activity of the SPS (C17S) mutant could be
detected in vivo is indicative of an essential component
present in E. coli that is absent in our in vitro
assay containing purified SPS and free selenide.
|
Competition Experiments-- The low amount of lyase required for detectable SPS activity suggests a complex may form between a NifS-like protein and SPS. This complex would allow the direct delivery of selenium as a putative Se0 to the active site of SPS. As a means of detecting complex formation with a NifS-like protein and SPS, competition assays were performed. As a potential competitor, a catalytically inactive mutant CsdB (R379A),3 which is unable to bind L-selenocysteine, was added to assay mixtures containing CsdB(1 µM), L-selenocysteine (10 mM), and SPS (10 µM). If SPS and CsdB actually bind to form a complex, then the addition of CsdB (R379A) would displace CsdB. To observe the possible competitive capability of CsdB (R379A), reaction mixtures were prepared that contained 0.25, 0.5, 1, 5, and 10 µM CsdB (R379A). The SPS selenium-dependent hydrolysis of ATP to AMP was measured in each sample. Over the range of added CsdB (R379A) examined, the observed rate of AMP formation was unaffected (data not shown), indicating that a 5-10-fold molar excess of this mutant is ineffective as a competitor of putative complex formation between SPS and the active delivery protein. Although no decrease in SPS activity was observed in the presence of excess CsdB (R379A), the substitution of alanine for arginine, which is known to affect selenocysteine binding, might also affect binding to SPS (23, 24). Because wild-type CsdB has both L-cysteine desulfurase and L-selenocysteine-lyase activities, it is possible that binding of L-selenocysteine induces a conformational change that allows complex formation with SPS, and this change cannot occur in the mutant.
Re-evaluation of the SPS (C17S) Mutant--
Previously, it was
shown that the SPS (C17S) mutant enzyme is unable to catalyze the
selenide dependent conversion of ATP to AMP (13). However, the ability
of the SPS (C17S) mutant to complement MBO8 in the in vivo
benzyl viologen overlay assay and incorporate selenocysteine
into FDHH suggests either free selenide in the in
vitro assay does not mimic the actual in vivo substrate or, alternatively, an additional factor is needed for selenophosphate formation and is supplied by MBO8. To determine whether a selenium delivery protein might be the factor required, the SPS (C17S) mutant
enzyme was assayed in the presence of a selenocysteine-lyase protein.
Fig. 3A shows that replacement
of free selenide with 10 µM CsdB, CSD, or IscS and
L-selenocysteine results in detectable activity in the SPS
(C17S) in vitro assay. Fig. 3B shows that in the
presence of a lyase (IscS), SPS (C17S) is saturated with Se0 and activity is detected. Maximum activity is observed
when concentrations of IscS approach one-half or greater the
concentration of SPS (C17S). In contrast, maximum activity of wild-type
SPS is observed in the presence of a selenium delivery protein at
concentrations as low as 0.25 µM. The ability to detect
catalytic activity of the SPS (C17S) mutant further supports the
involvement of a lyase protein in selenophosphate biosynthesis and
provides additional evidence that cysteine-17 of SPS does not have a
direct catalytic role.
|
Biological roles of NifS proteins include the mobilization of sulfur [S0] from cysteine to a specific protein acceptor. The mobilized sulfur can be distributed throughout the cell for iron-sulfur cluster assembly such as those found in nitrogenase (10, 11), FNR, SoxR (25, 26), and apodihydroxy acid dehydratase (27). NifS-like proteins have been identified in several organisms (28), and in some sources such as E. coli (29, 30), H. influenzae (31), and Synechocystis (32, 33) there are three nifS-like genes. Additional in vivo functions of NifS-like proteins including tRNA sufurtransferase activity in E. coli (34), NAD biosynthesis in Bacillus subtilis (35) and E. coli (36), tRNA splicing in Saccharomyces cerevisiae (37), and the biosynthesis of sulfur-containing cofactors such as biotin and thiamin have been determined (36, 38). These additional functions, together with the identification of multiple NifS-like proteins support roles for NifS-like proteins that are not limited to iron-sulfur cluster assembly.
The generation of Se0 by the NifS-like proteins reflects an
additional in vivo function in which these enzymes
participate as components of a selenium delivery system for the
biosynthesis of selenoproteins and selenium modification of tRNA
nucleosides (Fig. 4). The chemical
similarity between selenium and sulfur allows selenium to enter
bacterial metabolism via the cysteine biosynthetic pathway
where it can be incorporated into free selenocysteine (39). Free
selenocysteine can be inserted into proteins nonspecifically, in place
of cysteine, or a NifS-like protein can utilize it to generate selenium
for SPS. The biological relevance of the NifS-like proteins in
selenophosphate biosynthesis is particularly evident in the case of the
SPS (C17S) mutant. Catalytic activity of this mutated SPS enzyme could
be detected in the presence of CsdB, CSD, or IscS (Fig. 3). In the
in vitro coupled assays, all three E. coli
NifS-like proteins were able to function well as selenium delivery proteins with SPS. However, in vivo concentrations
of sulfur-containing compounds are much higher compared with their selenium analogs. For the E. coli NifS-like proteins to be
effective selenium delivery proteins under normal conditions
additional proteins may be involved to assist in the discrimination
between cysteine and selenocysteine. Future work will be focused on
identifying additional cellular components and proteins that
participate in selenium metabolism and selenophosphate biosynthesis.
Clearly, generation of Se0 at or in proximity to SPS may be
the mechanism whereby the essential substrate of the enzyme is made
available and the obstacle of free selenide toxicity is avoided.
|
| |
FOOTNOTES |
|---|
* This work was supported by a Short-term Invitation Fellowship for Research in Japan from the Japanese Society for the Promotion of Science (to G.M.L.).The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
§ To whom correspondence should be addressed: Laboratory of Biochemistry, NHLBI, National Institutes of Health, Bldg. 3-Rm. 103, 9000 Rockville Pike, Bethesda, MD 20892. Tel.: 301-496-3002; Fax: 301-496-0599; E-mail: lacourcg@nhlbi.nih.gov.
Published, JBC Papers in Press, May 26, 2000, DOI 10.1074/jbc.M000926200
2 L. Mullins, H. Walker, T. Stadtman, and F. Rauschel, unpublished results.
3 H. Mihara, T. Kurihara, and N. Esaki, unpublished results.
| |
ABBREVIATIONS |
|---|
The abbreviations used are: SPS, selenophosphate synthetase; NifS, cysteine desulfurase; CSD, cysteine sulfinate desulfinase; IscS, iron sulfur cluster; FDHH, formate dehydrogenase; Tricine, N-tris(hydroxymethyl)methylglycine.
| |
REFERENCES |
|---|
|
TOP
ABSTRACT
INTRODUCTION
EXPERIMENTAL PROCEDURES
RESULTS AND DISCUSSION
REFERENCES
|
|---|
| 1. | Leinfelder, W., Forchhammer, K., Veprek, B., Zehelein, E., and Böck, A. (1990) Proc. Natl. Acad. Sci. U. S. A. 87, 543-547 |
| 2. | Veres, Z., Tsai, L., Scholz, T. D., Politino, M., Balaban, R. S., and Stadtman, T. C. (1990) Proc. Natl. Acad. Sci. U. S. A. 89, 2975-2070 |
| 3. | Veres, Z., Kim, I. Y., Scholz, T. D., and Stadtman, T. C. (1994) J. Biol. Chem. 269, 10597-10603 |
| 4. | Lacourciere, G. M., and Stadtman, T. C. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 44-48 |
| 5. | Jacob, C., Maret, W., and Vallee, B. L. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 1910-1914 |
| 6. | Esaki, N., Nakamura, T., Tanaka, H., and Soda, K. (1982) J. Biol. Chem. 257, 4386-4391 |
| 7. | Chocat, P., Esaki, N., Tanizawa, K., Nakamura, K., Tanaka, H., and Soda, K (1985) J. Bacteriol. 163, 669-676 |
| 8. | Esaki, N., Seraneeprakarn, V., Tanaka, H., and Soda, K. (1988) J. Bacteriol. 170, 751-756 |
| 9. | Lacourciere, G. M., and Stadtman, T. C. (1998) J. Biol. Chem. 273, 3091-3096 |
| 10. | Zheng, L., White, R. H., Cash, V. L., Jack, R. F., and Dean, D. R. (1993) Proc. Natl. Acad. Sci. U. S. A. 90, 2754-2758 |
| 11. | Zheng, L., White, R. H., Cash, V. L., and Dean, D. R. (1994) Biochemistry 33, 4714-4720 |
| 12. | Mihara, H., Maeda, M., Fujii, T., Kurihara, T, Hata, Y., and Esaki, N. (1999) J. Biol. Chem. 274, 14768-14772 |
| 13. | Kim, I. Y., Veres, Z., and Stadtman, T. C. (1992) J. Biol. Chem. 267, 19650-19654 |
| 14. | Kim, I. Y., Veres, Z., and Stadtman, T. C. (1993) J. Biol. Chem. 268, 27020-27025 |
| 15. | Tanaka, H., and Soda, K. (1987) Methods Enzymol. 143, 240-243 |
| 16. | Leinfelder, W., Forchhammer, K., Zinoni, F., Sawers, G., Mandrand-Berthelot, M.-A., and Böck, A. (1988) J. Bacteriol. 170, 540-546 |
| 17. | Haddock, B. A., and Mandrand-Berthelot, M.-A. (1982) Biochem. Soc. Trans. 10, 478-480 |
| 18. | Peck, H. D., Jr., and Guest, H. (1957) J. Bacteriol. 73, 706-721 |
| 19. | Mandrand-Berthelot, M.-A., Wee, M. Y. K., and Haddock, B. A. (1978) FEMS Microbiol. Lett. 4, 36-40 |
| 20. | Walker, H., Ferretti, J. A., and Stadtman, T. C. (1998) Proc. Natl. Acad. Sci. U. S. A. 95, 2180-2185 |
| 21. | Forchhammer, K., Leinfelder, W., Boesmiller, K., Veprek, B., and Böck, A. (1991) J. Biol. Chem. 266, 6318-6323 |
| 22. | Stadtman, T. C., Davis, J. N., Zehelin, E., and Böck, A. (1989) Biofactors 2, 35-44 |
| 23. | Fujii, T., Maeda, M., Mihara, H., Kurihara, T., Esaki, N., and Hata, Y. (2000) Biochemistry 39, 1263-1273 |
| 24. | Mihara, H., Kurihara, T., Yoshimura, T., and Esaki, N. (2000) J. Biochem. 127, 559-567 |
| 25. | Green, J., Bennett, B., Jordan, P., Ralph, E. T., Thomson, A. J., and Guest, J. R. (1996) Biochem. J. 316, 887-892 |
| 26. | Hidalgo, E., and Demple, B. (1996) J. Biol. Chem. 271, 16068-16074 |
| 27. | Flint, D. H. (1996) J. Biol. Chem. 271, 16068-16074 |
| 28. | Mihara, H., Kurihara, T., Yoshimura, T., Soda, K., and Esaki, N. (1997) J. Biol. Chem. 272, 22417-22424 |
| 29. | Aiba, H., Baba, T., Hayashi, K., Inada, T., Isono, K., Kasai, H., Kashimoto, K., Kimura, S., Kitakawa, M., Kitagawa, M., Makino, K., Miki, T., Mizobuchi, K., Mori, H., Mori, T., Motomura, K., Makade, S., Nakamura, Y., Nashimoto, H., Nishio, Y., Oshima, T., Saito, N., Sampei, G., Seki, Y., Sivasundaram, S., Tagami, H., Takeda, J., Takemoto, K., Takeuchi, Y., Wada, C., Yamamoto, Y., and Horiuchi, T. (1996) DNA Res. 3, 363-377 |
| 30. | Yamamoto, Y., Aiba, H., Baba, T., Hayashi, K., Inada, T., Isono, K., Itoh, T., Kimura, S., Kitagawa, M., Makino, K., Miki, T., Mitsuhashi, N., Mizobuchi, K., Mori, H., Nakade, S., Nakamura, Y., Nashimoto, H., Oshima, T., Ouama, S., Saito, N., Sampei, G., Satoh, Y., Sivasundaram, S., Tagami, H., Takahashi, H., Takeda, J., Takemoto, K., Uehara, K., Wada, C., Yamagata, S., and Horiuchi, T. (1997) DNA Res. 4, 91-113 |
| 31. | Fleischmann, R. D., Adams, M. D., White, O., Clayton, R. A., Kirkness, E. F., Kerlavage, A. R., Bult, C. J., Tomb, J. F., Dougherty, B. A., Merrick, J. M., McKenney, K., Sutton, G., FitzHugh, W., Fields, C., Gocayne, J. D., Scott, J., Shirley, R., Liu, L. I., Glodek, A., Kelley, J. M., Weidman, J. F., Phillips, C. A., Spriggs, T., Hedblom, E., Cotton, M. D., Utterback, T. R., Hanna, M. C., Nguyen, D. T., Saudel, D. M., Brandon, R. C., Fine, L. D., Fritchman, J. L., Fuhrmann, J. L., Geoghagen, N. S. M., Gnehm, C. L., McDonald, L. A., Small, K. V., Fraser, C. M., Smith, H. O., and Venter, J. C. (1995) Science 269, 496-512 |
| 32. | Kaneko, T., Sato, S., Kotani, H., Tanaka, A., Asamizu, E., Nakamura, Y., Hosouchi, T., Matsuno, A., Muraki, A., Nakazaki, N., Naruo, K., Okumura, S., Shimpo, S., Takeuchi, C., Wada, T., Watanabe, A., Yamada, M., Yasuda, M., and Tabata, S. (1996) DNA Res. 3, 109-136 |
| 33. | Kaneko, T., Tanaka, A., Sato, S., Kotani, H., Sazuka, T., Miyajima, N., Sugiura, M., and Tabata, S. (1995) DNA Res. 2, 153-166 |
| 34. | Kambampati, R., and Lauhon, C. T. (1999) Biochemistry 38, 16561-16568 |
| 35. | Sun, D., and Setlow, P. (1993) J. Bacteriol. 175, 1423-1432 |
| 36. | Lauhon, C. T., and Kambampati, R. (2000) J. Biol. Chem. 275, 10727-10730 |
| 37. | Kolman, C., and Soll, D. (1993) J. Bacteriol. 175, 1433-1442 |
| 38. | Begley, T. P., Xi, J., Kinsland, C., Taylor, S., and McLafferty, F. (1999) Curr. Opin. Chem. Biol. 3, 623-629 |
| 39. | Muller, S., Heider, J., and Böck, A. (1997) Arch. Microbiol. 168, 421-427 |
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  T. Tamura, S. Yamamoto, M. Takahata, H. Sakaguchi, H. Tanaka, T. C. Stadtman, and K. Inagaki Selenophosphate synthetase genes from lung adenocarcinoma cells: Sps1 for recycling L-selenocysteine and Sps2 for selenite assimilation PNAS, November 16, 2004; 101(46): 16162 - 16167. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Pilon, J. D. Owen, G. F. Garifullina, T. Kurihara, H. Mihara, N. Esaki, and E. A.H. Pilon-Smits Enhanced Selenium Tolerance and Accumulation in Transgenic Arabidopsis Expressing a Mouse Selenocysteine Lyase Plant Physiology, March 1, 2003; 131(3): 1250 - 1257. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. T. Kaiser, S. Bruno, T. Clausen, R. Huber, F. Schiaretti, A. Mozzarelli, and D. Kessler Snapshots of the Cystine Lyase C-DES during Catalysis. STUDIES IN SOLUTION AND IN THE CRYSTALLINE STATE J. Biol. Chem., January 3, 2003; 278(1): 357 - 365. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Kobayashi, Y. Ogra, K. Ishiwata, H. Takayama, N. Aimi, and K. T. Suzuki Selenosugars are key and urinary metabolites for selenium excretion within the required to low-toxic range PNAS, December 10, 2002; 99(25): 15932 - 15936. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. A.H. Pilon-Smits, G. F. Garifullina, S. Abdel-Ghany, S.-I. Kato, H. Mihara, K. L. Hale, J. L. Burkhead, N. Esaki, T. Kurihara, and M. Pilon Characterization of a NifS-Like Chloroplast Protein from Arabidopsis. Implications for Its Role in Sulfur and Selenium Metabolism Plant Physiology, November 1, 2002; 130(3): 1309 - 1318. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Mihara, S.-i. Kato, G. M. Lacourciere, T. C. Stadtman, R. A. J. D. Kennedy, T. Kurihara, U. Tokumoto, Y. Takahashi, and N. Esaki The iscS gene is essential for the biosynthesis of 2-selenouridine in tRNA and the selenocysteine-containing formate dehydrogenase H PNAS, May 14, 2002; 99(10): 6679 - 6683. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. M. Lacourciere Selenium Is Mobilized In Vivo from Free Selenocysteine and Is Incorporated Specifically into Formate Dehydrogenase H and tRNA Nucleosides J. Bacteriol., April 1, 2002; 184(7): 1940 - 1946. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Bebien, G. Lagniel, J. Garin, D. Touati, A. Vermeglio, and J. Labarre Involvement of Superoxide Dismutases in the Response of Escherichia coli to Selenium Oxides J. Bacteriol., March 15, 2002; 184(6): 1556 - 1564. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Frazzon and D. R. Dean Feedback regulation of iron-sulfur cluster biosynthesis PNAS, December 18, 2001; 98(26): 14751 - 14753. [Full Text] [PDF]
|
|
|
|
|
|
Y. Ogasawara, G. Lacourciere, and T. C. Stadtman Formation of a selenium-substituted rhodanese by reaction with selenite and glutathione: Possible role of a protein perselenide in a selenium delivery system PNAS, August 1, 2001; (2001) 171320998. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Ogasawara, G. Lacourciere, and T. C. Stadtman Formation of a selenium-substituted rhodanese by reaction with selenite and glutathione: Possible role of a protein perselenide in a selenium delivery system PNAS, August 14, 2001; 98(17): 9494 - 9498. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |
