diff --git a/docs/enzymes.rst b/docs/enzymes.rst
index 7c345c9726bdad1b6fb85221071a44943ed20bbc..e61cede6421edfc8d0567c13475448ff4abffbee 100644
--- a/docs/enzymes.rst
+++ b/docs/enzymes.rst
@@ -801,7 +801,7 @@ More information: https://web.expasy.org/peptide_cutter/peptidecutter_enzymes.ht
 Thrombin SG
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-This thrombin (Sequencing Grade) preferentially cleaves after R (`P1`) preceded by P in `P2`, V in `P3` and L in `P4` and followed by G in `P1'` and S `P2'`.
+This thrombin (Sequencing Grade) preferentially cleaves after R (`P1`) preceded by P in `P2`, V in `P3` and L in `P4` and followed by G in `P1'` and S in `P2'`.
 
 This thrombin is defined in several kits (see below).