Попробуйте это:
import itertools
userID, fname, lname, email, salary = [], [], [], [], []
lists = itertools.cycle([userID, fname, lname, email, salary])
with open("in_file.txt") as infile:
for line, append_list in zip(infile, lists):
append_list.append(line)
Ваши списки должны быть заполнены.