diff --git a/package-lock.json b/package-lock.json
index fc5e17bc8ab916020b19cb523d000de94208d138..2d9548bdff7f5fffa8c02a7f74ba16002110cd19 100644
Binary files a/package-lock.json and b/package-lock.json differ
diff --git a/src/mol-data/db/table.ts b/src/mol-data/db/table.ts
index 6335e37ed50eef0e761a90549ed53590e219647b..ae9b77cecb234164a676b62a677f291548e627ca 100644
--- a/src/mol-data/db/table.ts
+++ b/src/mol-data/db/table.ts
@@ -89,7 +89,7 @@ namespace Table {
     }
 
     export function columnToArray<S extends Schema>(table: Table<S>, name: keyof S, array?: Column.ArrayCtor<any>) {
-        table[name] = Column.asArrayColumn(table[name], array);
+        (table as Columns<S>)[name] = Column.asArrayColumn((table as Columns<S>)[name], array);
     }
 
     /** Sort and return a new table */