Plastid Class I and Cytosol Class II Aldolase of Euglena gracilis (Purification and Characterization)

Pelzer-Reith, Birgit; Wiegand, Sabine; Schnarrenberger, Claus

doi:10.1104/pp.106.3.1137

Cited by 29 publications

(14 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The latter is supported by comparisons of available crystal structures of rabbit muscle Class I and Escherichia coli Class II FBP aldolases indicating that even though both classes adopt a common folding topology ((␤␣) 8 triose-phosphate isomerase (TIM)-barrel fold) and catalyze identical reactions, they share no conserved catalytic residues, and the location of their active sites is distinct (12). However, more recent analysis combining sequence, structure, and functional information indicates that many of the (␤␣) 8 (TIM) barrel superfamilies, such as aldolases, TIMs, and enolases, share a common evolutionary origin (ancestral ␤/␣ barrel), although they adopt a wide range of enzymatic functions (13,14).…”

mentioning

confidence: 63%

“…Blast search). However, by closer inspection, sequence signatures could be identified resembling the active site region (position 177, T. tenax) and the phosphatebinding motif (position 203-204, T. tenax) of some members of the (␣␤) 8 TIM barrel superfamilies (13), strongly suggesting that this new family of Class I FBP aldolases is at least distantly related to classical Class I FBP aldolases. Moreover, secondary structure predictions (47, 48) performed with the aldolase sequences of T. tenax, P. furiosus, and Sulfolobus solfataricus not only identified these enzymes as (␣␤) 8 barrel proteins but also locate the functionally important residues at equivalent positions to the ones found in classical Class I FBP aldolases as well as in other enzymes of the (␣␤) 8 TIM barrel superfamilies (active site lysine in ␤ 6 , phosphate binding region at the end of ␤ 7 ; Fig.…”

Section: Nucleotide Sequence Of the Fba Genes Of T Tenax And Pmentioning

confidence: 99%

“…These non-significant average sequence similarities as well as the absence of certain DhnA-typical motifs in classical Class I enzymes characterize this new family of Class I FBP aldolases as a very divergent, new type in addition to classical Class I aldolases. However, both types of Class I FBP aldolases like other (␤␣) 8 (TIM) barrel proteins share, beside the predicted similar secondary structure arrangement, basic common sequence features in regions flanking the active site lysine or engaged in phosphate binding (13,57).…”

Section: Transcription Of the Fba Genes Of T Tenax And P Furiosus mentioning

confidence: 99%

“…Sequence comparisons of Class I and II FBP aldolases revealed no detectable sequence homology, suggesting convergent evolution (4,5,(7)(8)(9)(10)(11). The latter is supported by comparisons of available crystal structures of rabbit muscle Class I and Escherichia coli Class II FBP aldolases indicating that even though both classes adopt a common folding topology ((␤␣) 8 triose-phosphate isomerase (TIM)-barrel fold) and catalyze identical reactions, they share no conserved catalytic residues, and the location of their active sites is distinct (12).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Archaeal Fructose-1,6-bisphosphate Aldolases Constitute a New Family of Archaeal Type Class I Aldolase

Siebers

Brinkmann

Dörr

et al. 2001

Journal of Biological Chemistry

101

102

View full text Add to dashboard Cite

Fructose-1,6-bisphosphate (FBP) aldolase activity has been detected previously in several Archaea. However, no obvious orthologs of the bacterial and eucaryal Class I and II FBP aldolases have yet been identified in sequenced archaeal genomes. Based on a recently described novel type of bacterial aldolase, we report on the identification and molecular characterization of the first archaeal FBP aldolases. We have analyzed the FBP aldolases of two hyperthermophilic Archaea, the facultatively heterotrophic Crenarchaeon Thermoproteus tenax and the obligately heterotrophic Euryarchaeon Pyrococcus furiosus. For enzymatic studies the fba genes of T. tenax and P. furiosus were expressed in Escherichia coli. The recombinant FBP aldolases show preferred substrate specificity for FBP in the catabolic direction and exhibit metal-independent Class I FBP aldolase activity via a Schiff-base mechanism. Transcript analyses reveal that the expression of both archaeal genes is induced during sugar fermentation. Remarkably, the fbp gene of T. tenax is co-transcribed with the pfp gene that codes for the reversible PP i -dependent phosphofructokinase. As revealed by phylogenetic analyses, orthologs of the T. tenax and P. furiosus enzyme appear to be present in almost all sequenced archaeal genomes, as well as in some bacterial genomes, strongly suggesting that this new enzyme family represents the typical archaeal FBP aldolase. Because this new family shows no significant sequence similarity to classical Class I and II enzymes, a new name is proposed, archaeal type Class I FBP aldolases (FBP aldolase Class IA).Fructose-1,6-bisphosphate (FBP) 1 aldolase (EC 4.1.2.13) catalyzes the reversible aldol condensation of glyceraldehyde 3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP) yielding FBP. The enzyme fulfills an amphibolic function being involved in catabolic (glycolysis) as well as anabolic pathways (gluconeogenesis and Calvin cycle). In spite of this central function in carbohydrate metabolism, up to now no archaeal genes coding for the respective enzyme activities have been analyzed.Two distinct classes of FBP aldolases occur in nature, which differ in their enzymatic mechanisms (1-4). Class I FBP aldolases form a Schiff-base intermediate between the carbonyl substrate (FBP and DHAP) and the ⑀-amino group of the active site lysine residue and are inactivated by borohydride (NaBH 4 ), whereas Class II FBP aldolases depend on divalent metal ions to stabilize the carbanion intermediate and are, therefore, inhibited by EDTA. Class II enzymes of bacterial and eucaryal origin generally form dimers with a subunit molecular mass of ϳ40 kDa, whereas the Class I pendants are heterogeneous. Eucaryal aldolases are homomeric tetramers with a subunit molecular mass of ϳ40 kDa, and for bacterial enzymes oligomeric arrangements from monomer to decamer and subunit molecular masses of 27-40 kDa have been described (5, 6).Sequence comparisons of Class I and II FBP aldolases revealed no detectable sequence homology, suggesting convergent evolut...

show abstract

mentioning

confidence: 63%

Section: Nucleotide Sequence Of the Fba Genes Of T Tenax And Pmentioning

confidence: 99%

Section: Transcription Of the Fba Genes Of T Tenax And P Furiosus mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Archaeal Fructose-1,6-bisphosphate Aldolases Constitute a New Family of Archaeal Type Class I Aldolase

Siebers

Brinkmann

Dörr

et al. 2001

Journal of Biological Chemistry

101

102

View full text Add to dashboard Cite

show abstract

“…Whether a class I FBP aldolase is used during the heterotrophic growth of these bacteria is unknown. The opposite situation exists in the algae Chlamydomonas mundana and Euglena gracilis, which use a class II FBP aldolase for heterotrophic metabolism and, like higher plants (20), employ a class I FBP aldolase in the Calvin cycle (9,32,34). Escherichia coli contains a constitutive class II FBP aldolase, whereas a class I enzyme is induced by gluconeogenic growth conditions (37).…”

mentioning

confidence: 99%

Primary structure and phylogeny of the Calvin cycle enzymes transketolase and fructosebisphosphate aldolase of Xanthobacter flavus

et al. 1996

View full text Add to dashboard Cite

Xanthobacter flavus grows autotrophically by using the Calvin cycle for the fixation of CO 2 . Only 2 of the 11 enzymes of the Calvin cycle are characteristic for this pathway; the others are also present during heterotrophic growth. The key enzymes of the Calvin cycle, phosphoribulokinase and ribulosebisphosphate carboxylase, are encoded within the cbb operon, which is transcribed only during autotrophic growth. Two additional genes are located within this operon: cbbX, encoding a protein with unknown function, and cbbF, encoding fructosebisphosphatase (27,29). The transcription of the cbb operon is positively regulated by CbbR, a LysR-type transcriptional regulator, which binds to two sites in the cbb promoter (47).During autotrophic growth, X. flavus uses two fructosebisphosphatase enzymes with distinct properties. The inducible enzyme encoded by cbbF has a high level of sedoheptulosebisphosphatase activity and is stimulated by ATP. The second constitutive fructosebisphosphatase has a low level of sedoheptulosebisphosphatase activity and is not stimulated by ATP (48). In contrast to the fructosebisphosphatase isoenzyme pair, only one phoshoglycerate kinase gene, which is not encoded within the cbb operon, is employed by X. flavus. The pgk gene is constitutively expressed, but the expression level is higher during autotrophic growth than during heterotrophic growth (26).Little is known about the transketolase (EC 2.2.1.1) and fructosebisphosphate aldolase (FBP aldolase; EC 4.1.2.13) enzymes of X. flavus. Like fructosebisphosphatase and phosphoglycerate kinase, these enzymes are involved in both heterotrophic metabolism and the fixation of CO 2 via the Calvin cycle. Two unrelated mechanistically distinct types of FBP aldolase enzymes are encountered in bacteria, archaea, and eukarya (24). Class I FBP aldolases form a covalent Schiff base between the substrate and the ␣-amino group of a lysine residue during catalysis, whereas the class II enzymes depend on a divalent cation as the electrophile in the catalytic cycle (24).X. flavus (Table 1) was grown heterotrophically on succinate (10 mM) or gluconate (10 mM) and autotrophically on methanol (0.5% [vol/vol]) at 30ЊC as described previously (22,28). The activities of transketolase and FBP aldolase were determined, according to published methods (15, 49), in cell extracts which were prepared by using a French pressure cell as described previously (27). The activity of transketolase was increased sixfold following autotrophic growth on methanol compared with that of heterotrophically grown cells. In sharp contrast, the activity of FBP aldolase (without Fe 2ϩ ) was the same for both heterotrophic and autotrophic growth. Because the activity of class II FBP aldolase is dependent on Fe 2ϩ as the electrophile (24), FeSO 4 (700 M) was included in the reaction assay. Surprisingly, Fe 2ϩ did not affect the FBP aldolase activity in the cell extracts of heterotrophically grown cells but stimulated the activity of FBP aldolase in cell extracts of autotrophically grown cells ...

show abstract

Control of Carbon Fixation in Chloroplasts

Gontero¹,

Avilán²,

Lebreton³

Control of Primary Metabolism in Plants

View full text Add to dashboard Cite

Plastid Class I and Cytosol Class II Aldolase of Euglena gracilis (Purification and Characterization)

Cited by 29 publications

References 27 publications

Archaeal Fructose-1,6-bisphosphate Aldolases Constitute a New Family of Archaeal Type Class I Aldolase

Archaeal Fructose-1,6-bisphosphate Aldolases Constitute a New Family of Archaeal Type Class I Aldolase

Primary structure and phylogeny of the Calvin cycle enzymes transketolase and fructosebisphosphate aldolase of Xanthobacter flavus

Control of Carbon Fixation in Chloroplasts

Contact Info

Product

Resources

About