Table 4 Glycosylation of hydroxylysine residues estimated by mass spectrometry of non-cross-linked glycosylated residues.

From: Lysyl hydroxylase 2 mediated collagen post-translational modifications and functional outcomes

  

Site occupancy (%)

MC

EV

KO-1

KO-2

KO-3

α1(I) K87

Hyl

4.0 ± 0.2

3.3 ± 0.1

13.0 ± 0.3***,###

12.6 ± 0.2***,###

5.3 ± 0.1***,###

Glycosylated-Hyl

96.0 ± 0.2

96.7 ± 0.1

87.0 ± 0.3***,###

87.4 ± 0.2***,###

94.7 ± 0.1**,###

α1(I) K99

Hyl

65.3 ± 0.5

67.0 ± 0.6

74.5 ± 0.2***,###

73.5 ± 0.6***,###

76.5 ± 0.1***,###

Glycosylated-Hyl

34.7 ± 0.5

33.0 ± 0.6

25.5 ± 0.2***,###

26.5 ± 0.6***,###

23.5 ± 0.1***,###

α1(I) K174

Hyl

88.3 ± 1.0

89.7 ± 0.4

92.7 ± 0.5***,###

92.2 ± 0.2***,###

91.0 ± 0.2***

Glycosylated-Hyl

11.7 ± 1.0

10.3 ± 0.4

7.3 ± 0.5***,###

7.8 ± 0.2***,###

9.0 ± 0.2***

α1(I) K564

Hyl

72.3 ± 0.9

75.2 ± 0.2

84.3 ± 0.3***,###

83.8 ± 0.5***,###

84.2 ± 0.2***,###

Glycosylated-Hyl

27.7 ± 0.9

24.8 ± 0.2

15.7 ± 0.3***,###

16.2 ± 0.5***,###

15.8 ± 0.2***,###

α2(I) K174

Hyl

9.7 ± 0.5

9.2 ± 0.7

15.6 ± 0.8***,###

16.0 ± 1.1***,###

7.7 ± 0.1*

Glycosylated-Hyl

90.3 ± 0.5

90.8 ± 0.7

84.4 ± 0.8***,###

84.0 ± 1.1***,###

92.3 ± 0.1*

α2(I) K219

Hyl

94.3 ± 1.3

94.4 ± 0.8

96.8 ± 0.2**,##

96.9 ± 0.5**,##

94.9 ± 0.2

Glycosylated-Hyl

5.7 ± 1.3

5.6 ± 0.8

3.2 ± 0.2**,##

3.1 ± 0.5**,##

5.1 ± 0.2

  1. Glycosylation of Hyl residues (%) represents the relative levels of Glycosylated Hyl (G-Hyl + GG-Hyl). Hyl + Glycosylated Hyl = 100%.
  2. Values represent mean ± S.D. (n = 3) of triplicate analysis for each group. Statistical differences were determined by Kruskal–Wallis one-way analysis of variance and means comparison with the controls by Dunnett’s method.
  3. Hyl hydroxylysine, G- galactosyl-, GG- glucosylgalactosyl-, MC MC3T3-E1, EV empty vector, KO knock-out.
  4. *p < 0.05, **p < 0.01, and ***p < 0.001 between MC and KO; ##p < 0.01 and ###p < 0.001 between EV and KO, respectively.