diff --git a/bin/2.2_motif_estimation/label_cluster.R b/bin/2.2_motif_estimation/label_cluster.R
index b00a97a..60f1ec8 100644
--- a/bin/2.2_motif_estimation/label_cluster.R
+++ b/bin/2.2_motif_estimation/label_cluster.R
@@ -7,7 +7,8 @@ option_list <- list(
 )
 
 opt_parser <- OptionParser(option_list = option_list, 
-                           description = "Adding Cluster ID to Query_ID Column")
+                           description = "Adding Cluster ID to Query_ID Column.",
+                           epilogue = "Author: Rene Wiegandt <Rene.Wiegandt@mpi-bn.mpg.de>")
 
 opt <- parse_args(opt_parser)
 
@@ -27,7 +28,7 @@ label_cluster <- function(input, output){
   cluster_number <- as.numeric(splitted_name[length(splitted_name) - 1]) + 1
   
   #Adding cluster ID to first column
-  tsv$Query_ID <- paste(tsv$Query_ID, ".", cluster_number,sep = "")
+  tsv$Query_ID <- paste0(tsv$Query_ID, ".", cluster_number)
   
   
   data.table::fwrite(tsv, file = output, sep = "\t", col.names = FALSE)
@@ -36,4 +37,4 @@ label_cluster <- function(input, output){
 # run function label_cluster with given parameteres if not in interactive context (e.g. run from shell)
 if (!interactive()) {
   label_cluster(opt$input, opt$output)
-}
\ No newline at end of file
+}