[1] Johannes made her international debut at the 2005 IAAF World Cross Country Championships, where she finished 80th in the women's long race.

[4] She again represented her country on the global stage at the 2009 World Championships in Athletics but finished 56th in a slow time of 2:50:19 hours.

[6] At the 2012 Summer Olympics, Johannes knocked more than a minute off that personal best, finishing in 12th with a new best of 2:26:09 – a Namibian record.

Johannes completed the 42,2 km marathon in 2 hours 32 minutes 40 seconds to finish well ahead of second-placed Lisa Weightman of Australia (2:33:23), while another Australian, Jess Trengrove, won bronze in 2:34:09.

[10] Her husband, Japhet Uutoni, also won a gold medal for Namibia in boxing at the 2006 Commonwealth Games.

She then broke the Namibian half-marathon record in April at the Two Oceans Half Marathon in Cape Town, running a winning time of 1:10:30.

[10] In September, she achieved her greatest career landmark by earning a medal at the Athletics World Championships for her third place in the marathon.