diff --git a/api/tests/integration/ref/formats/fasta_to_ket.py.out b/api/tests/integration/ref/formats/fasta_to_ket.py.out
index 45b7ca234f..0fb5130d3f 100644
--- a/api/tests/integration/ref/formats/fasta_to_ket.py.out
+++ b/api/tests/integration/ref/formats/fasta_to_ket.py.out
@@ -4,6 +4,6 @@ test_rna.ket:SUCCEED
 test_dna.ket:SUCCEED
 multiseq.ket:SUCCEED
 break_peptide.ket:SUCCEED
-break_rna.fasta:SEQUENCE loader: SequenceLoader::loadFasta(), Invalid symbols in the sequence: *
+break_rna.fasta:SEQUENCE loader: Invalid symbols in the sequence: *
 comment.ket:SUCCEED
 test_1881.ket:SUCCEED
diff --git a/api/tests/integration/ref/formats/idt_to_ket.py.out b/api/tests/integration/ref/formats/idt_to_ket.py.out
index 1ec6eabb6c..ca4c32738c 100644
--- a/api/tests/integration/ref/formats/idt_to_ket.py.out
+++ b/api/tests/integration/ref/formats/idt_to_ket.py.out
@@ -9,7 +9,7 @@ idt_prefix_suffix.ket:SUCCEED
 idt_singe_32moera_nucleoside.ket:SUCCEED
 idt_single_nucleoside.ket:SUCCEED
 idt_std_phosphates.ket:SUCCEED
-Test '!+-$#12w12r23e32e33': got expected error 'SequenceLoader::loadIdt(), Invalid symbols in the sequence: !,-,$,#,1,2,w,1,2,2,3,e,3,2,e,3,3'
+Test '!+-$#12w12r23e32e33': got expected error 'Invalid symbols in the sequence: !,-,$,#,1,2,w,1,2,2,3,e,3,2,e,3,3'
 Test '+/5Phos/A': got expected error 'Sugar prefix could not be used with '/5Phos/''
 Test '/': got expected error 'Unexpected end of data'
 Test '//': got expected error 'Invalid modification: empty string.'
diff --git a/api/tests/integration/tests/formats/idt_to_ket.py b/api/tests/integration/tests/formats/idt_to_ket.py
index 02358cfe74..5c595478bf 100644
--- a/api/tests/integration/tests/formats/idt_to_ket.py
+++ b/api/tests/integration/tests/formats/idt_to_ket.py
@@ -60,7 +60,7 @@ def find_diff(a, b):
         print(diff)
 
 idt_errors = {
-    "!+-$#12w12r23e32e33": "SequenceLoader::loadIdt(), Invalid symbols in the sequence: !,-,$,#,1,2,w,1,2,2,3,e,3,2,e,3,3",
+    "!+-$#12w12r23e32e33": "Invalid symbols in the sequence: !,-,$,#,1,2,w,1,2,2,3,e,3,2,e,3,3",
     "/": "Unexpected end of data",
     "//": "Invalid modification: empty string.",
     "/a/": "Invalid modification: a.",
diff --git a/core/indigo-core/molecule/src/sequence_loader.cpp b/core/indigo-core/molecule/src/sequence_loader.cpp
index 9a1b373491..975a6fbfdb 100644
--- a/core/indigo-core/molecule/src/sequence_loader.cpp
+++ b/core/indigo-core/molecule/src/sequence_loader.cpp
@@ -116,7 +116,7 @@ void SequenceLoader::loadFasta(BaseMolecule& mol, SeqType seq_type)
             }
 
             if (invalid_symbols.size())
-                throw Error("SequenceLoader::loadFasta(), Invalid symbols in the sequence: %s", invalid_symbols.c_str());
+                throw Error("Invalid symbols in the sequence: %s", invalid_symbols.c_str());
 
             if (!properties.is_empty())
             {
@@ -198,7 +198,7 @@ void SequenceLoader::loadSequence(BaseMolecule& mol, SeqType seq_type)
     }
 
     if (invalid_symbols.size())
-        throw Error("SequenceLoader::loadSequence(), Invalid symbols in the sequence: %s", invalid_symbols.c_str());
+        throw Error("Invalid symbols in the sequence: %s", invalid_symbols.c_str());
 }
 
 bool SequenceLoader::addTemplate(BaseMolecule& mol, const std::string alias, MonomerClass mon_type)
@@ -560,5 +560,5 @@ void SequenceLoader::loadIdt(BaseMolecule& mol)
     }
 
     if (invalid_symbols.size())
-        throw Error("SequenceLoader::loadIdt(), Invalid symbols in the sequence: %s", invalid_symbols.c_str());
+        throw Error("Invalid symbols in the sequence: %s", invalid_symbols.c_str());
 }