Additional 109th bead is knotted to the mala. It is called by different names Sumeru, Meru bead, Guru bead etc.
https://freeglobaluniversity.blogspot.com/search/label/Meru
To show respect to the Master(Guru), Guru bead is never crossed when counting the mantras during meditation. Instead, the mala is turned around so that the next round of counting begins with the 108th bead. The Guru bead is separate from the main mala.
https://freeglobaluniversity.blogspot.com/search/label/YantraMantraTantra
As discussed earlier, main mala of 108 beads makes the universe. Since Guru bead is separate from the main mala(i.e. universe), it suggests that the Universal Self is transcendental, i.e. beyond the universe. The name of 109th bead is Guru bead. It is separate from the universe of 108 beads. It means that Guru is the force beyond the universe and is nothing but the Universal Self that directs everything. It means that Guru is nothing but God.
http://discoveryuniverse.blogspot.com/search/label/108
The tassel after the Guru bead indicates the fourth state called Turiya. It is a transcendental state beyond three states, viz., waking, dream and deep sleep.
https://freeglobaluniversity.blogspot.com/search/label/OMAmenAmeen