Figure 4: The hydrogen bonds between Tln-S339 and Tln-E353, Tln-K327 and Int-D759, and Tln-N326 and Int-R760 contribute to their affinity to β1-integrins.

(A) Tracked distance of the intra-molecular hydrogen bond formed by residue S336/339 and E350/353 of talin. Black, blue, and red tracks represent the distance (Unit in Å) between the Hɣ atom of S339/C336/S336 and the Oε atom of E353/350 in talin2^WT/integrin, talin1^WT/integrin, and talin1^C336S/integrin complexes, respectively. (B) Tracked distance of the inter-molecular hydrogen bond formed between the positive-charged side chain of K324/327 in talin and the negative charged side chain of D759 in β1-integrin. Black, blue, and red tracks represent the distance between the Hζ atom of K327/324 of talin and the Oδ atom at D759 of β1-integrin in talin2^WT/integrin, talin1^WT/integrin, talin1^C336S/integrin complexes, respectively. (C) Tracked distance of the inter-molecular hydrogen bond formed between the side chain of N323/326 in talin and side chain of R760 in β1-integrin. Black, blue, and red tracks represent the distance between the Oδ atom of N326/323 of talin and the Hη atom of R760 of β1-integrin in talin2^WT/integrin, talin1^WT/integrin, and talin1^C336S/integrin complexes, respectively. (D) Hydrogen bond between S339 and E353 of talin with labeled distance in talin2^WT/integrin complex. Talin is represent as cyan ribbons. S339 and E353 are shown in golden stick-ball style. (E) Side chains of C336 and E350 are far away from each other in talin1^WT/integrin complex. (F) Hydrogen bond between S336 and E350 with labeled distance in talin1^C336S/integrin complex. (G) Hydrogen bond between Tln-K327 and Int-D759, and Tln-N326 and Int-R760 with labeled distance in talin2^WT/integrin complex. Talin and β1-integrin are presented as cyan ribbons and green ribbons respectively. (H) Side chains of Tln-K324, Tln-N323, Int-D759, and Int-R760 are far away from each other in talin1^WT/integrin complex. (I) Hydrogen bond between Tln-K324 and Int-D759, and Tln-N323 and Int-R760 with labeled distance in talin1^C336S/integrin complex.