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Table 1 Starch metabolic enzyme activities in soluble leaf extracts

From: Overlapping functions of the starch synthases SSII and SSIII in amylopectin biosynthesis in Arabidopsis

Enzyme

Activity by genotype

 

Wild type

Atss2-1

Atss3-1

Atss2/Atss3

SSa

212 ± 8.66 (4)

237 ± 8.74 (4)

265 ± 18.6 (4)

190 ± 8.78 (4)

SS

9.24 ± 0.80 (2)

9.19 ± 0.16 (2)

9.82 ± 0.07 (2)

9.85 ± 0.41 (2)

SBEb

50.3 ± 7 (1)

52.6 ± 9.9 (1)

45.8 ± 5.7 (1)

51.5 ± 10.0 (1)

ADPGPP

15.5 ± 3.8 (3)

19.9 ± 3.1 (3)

14.5 ± 2.4 (3)

14.5 ± 2.5 (3)

ADPGPP + 3PGA

35.3 ± 1.8 (3)

33.7 ± 4.0 (3)

22.1 ± 6.9 (3)

23.2 ± 13.0 (3)

α-amylase

32.6 ± 2.0 (3)

33.7 ± 3.4 (3)

35.5 ± 1.3 (3)

44.1 ± 3.7 (3)

β-amylase

191 ± 27 (3)

237 ± 46 (3)

259 ± 22 (3)

243 ± 30 (3)

Pullulanase-type DBE

8.40 ± 1.7 (3)

15.4 ± 1.8 (3)

2.06 ± 0.34 (3)c

3.90 ± 1.9 (3)

DE

25.6 ± 5.8 (3)

29.3 ± 3.0 (3)

30.4 ± 0.65 (3)

32.8 ± 1.8 (3)

Maltase

42.5 ± 4.7 (3)

37.6 ± 0.59 (3)

40.5 ± 4.9 (3)

38.5 ± 9.8 (3)

SPb

1.34 ± 0.20 (1)

2.86 ± 0.22 (1)

0.70 ± 0.35 (1)

0.97 ± 0.08 (1)

  1. Unless otherwise noted, units are nmol product/min/mg protein. Values in parentheses indicate the number of independent biological replicates used to generate the mean and standard error values indicated.
  2. Abbreviations are as follows: DE: disproportionating enzyme; SP, starch phosphorylase; ADPGPP: ADPGlc pyrophosphorylase; DBE: starch debranching enzyme; 3PGA: 3-phosphoglycerate.
  3. a SS activity was measured independently in two completely separate sets of assays. For the assays in this row only the units are nmol glucose incorporated/g FW/min.
  4. b The values for SP and BE activity were determined by triplicate measurements from a single plant extract.
  5. c Value is significantly different from wild type after Dunnet's adjustment for multiple comparisons. Unless so indicated, values are not significantly different from wild type.