diff --git a/kleborate/truncation.py b/kleborate/truncation.py
index 93186a0..92793c0 100644
--- a/kleborate/truncation.py
+++ b/kleborate/truncation.py
@@ -13,7 +13,6 @@
 """
 
 from Bio.Seq import Seq
-from Bio.Alphabet import IUPAC
 
 from .misc import reverse_complement
 
@@ -51,7 +50,7 @@ def truncation_check(hit, cov_threshold=90.0):
     # denominator for coverage.
     ref_aa_length = (hit.ref_length - 3) // 3
 
-    coding_dna = Seq(nucl_seq, IUPAC.unambiguous_dna)
+    coding_dna = Seq(nucl_seq)
     translation = str(coding_dna.translate(table='Bacterial', to_stop=True))
 
     coverage = 100.0 * len(translation) / ref_aa_length