diff --git a/src/naming_conventions.jl b/src/naming_conventions.jl
index e59dffe..4cfc77e 100644
--- a/src/naming_conventions.jl
+++ b/src/naming_conventions.jl
@@ -166,9 +166,12 @@ Check the status of a Uniprot ID mapping job. Returns `true` if the results are
 ready. Otherwise, returns the status object.
 """
 function map_uniprot_status(jobID)
-    resp = HTTP.get("https://rest.uniprot.org/idmapping/status/$jobID", ["Accept" => "application/json"]; decompress = true)
+    # `decompress = false` suppresses the `Accept-Encoding: gzip` request header, so the
+    # body arrives as plain text. Uniprot does not always honor a compression request, and
+    # unconditionally gunzipping the response fails whenever it returns one uncompressed.
+    resp = HTTP.get("https://rest.uniprot.org/idmapping/status/$jobID", ["Accept" => "application/json"]; decompress = false)
     if resp.status == 200
-        status = JSON3.read(String(HTTP.decode(resp)))
+        status = JSON3.read(String(resp.body))
         haskey(status, "results") && return true
         return status
     end
@@ -181,9 +184,9 @@ end
 Retrieve the results of a Uniprot ID mapping job.
 """
 function map_uniprot_retrieve(jobID)
-    resp = HTTP.get("https://rest.uniprot.org/idmapping/stream/$jobID", ["Accept" => "application/json"]; decompress = true)
+    resp = HTTP.get("https://rest.uniprot.org/idmapping/stream/$jobID", ["Accept" => "application/json"]; decompress = false)
     if resp.status == 200
-        return JSON3.read(String(HTTP.decode(resp)))
+        return JSON3.read(String(resp.body))
     end
     return nothing
 end
diff --git a/test/runtests.jl b/test/runtests.jl
index 8375643..4a120bc 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -418,7 +418,9 @@ using Test
                 end
             end
             @test startswith(query_ebi_proteins("Q7TQA6"; format=:fasta), ">sp|Q7TQA6")
-            @test count(==('>'), query_ebi_proteins(["C3N734", "H2C869", "Q3V4T1", "P20220"]; format=:fasta)) == 4
+            # Reviewed (SwissProt) accessions: unreviewed entries get withdrawn when
+            # the underlying genome annotation changes, silently shrinking the count.
+            @test count(==('>'), query_ebi_proteins(["P29274", "P29275", "P15409", "Q7TQA6"]; format=:fasta)) == 4
             q = query_ncbi(obj)
             @test q["total_count"] == 1
         end