Histatins

from Wikipedia, the free encyclopedia

Histatins are proteins found in the saliva of some mammals . They inhibit bacterial proteases and promote wound healing in the oral mucosa . They are involved in the structure of the outermost protein layer of the tooth enamel (English pellicle ). Histatins and statherins, which stabilize calcium levels in saliva, belong to a family of similar proteins.

Classification

In humans, a distinction is made between up to 26 different histatins, most of which consist of 20–40 amino acids. Twelve of these were numbered systematically as histatin-1 to histatin-12. The most important are histatin-1, -3 and -5, which together make up 85 to 90 percent of the total amount of histatin.

The 12 histatins are encoded by two genes , HTN1 and HTN3 , and are cut from the 57 and 51 amino acid long precursors with the help of proteases : 

        10         20         30         40         50 
MKFFVFALVL ALMISMISAD SHEKRHHGYR RKFHEKHHSH REFPFYGDYG SNYLYDN   HTN1 Genprodukt
                    D SHEKRHHGYR RKFHEKHHSH REFPFYGDYG SNYLYDN   Histatin-1
                                 RKFHEKHHSH REFPFYGDYG SNYLYDN   Histatin-2

        10         20         30         40         50 
MKFFVFALIL ALMLSMTGAD SHAKRHHGYK RKFHEKHHSH RGYRSNYLYD N         HTN3 Genprodukt
                    D SHAKRHHGYK RKFHEKHHSH RGYRSNYLYD N         Histatin-3
                                 RKFHEKHHSH RGYRSNYLYD N         Histatin-4
                    D SHAKRHHGYK RKFHEKHHSH RGY                  Histatin-5
                    D SHAKRHHGYK RKFHEKHHSH RGYR                 Histatin-6
                                 RKFHEKHHSH RGY                  Histatin-7
                                  KFHEKHHSH RGY                  Histatin-8
                                 RKFHEKHHSH RGYR                 Histatin-9
                                  KFHEKHHSH RGYR                 Histatin-10
                         KRHHGYK R                               Histatin-11
                         KRHHGYK                                 Histatin-12

background

Histatins are cationic proteins that are rich in histidine . They inhibit bacterial proteases and have an antimicrobial and fungistatic effect . Hence the recommendation to wet your own wounds with saliva if nothing else is available.

Individual evidence

  1. ↑ Oudhoff MJ, Bolscher JG, Nazmi K, et al. : Histatins are the major wound-closure stimulating factors in human saliva as identified in a cell culture assay . In: FASEB J . . 22, No. 11, November 2008, pp. 3805-3812. doi : 10.1096 / fj.08-112003 . PMID 18650243 .
  2. ↑ a b search result UniProt histatin / statherin family .
  3. ^ Histatins.  In: Online Mendelian Inheritance in Man . (English).
  4. ↑ Why licking wounds helps. In: Wissenschaft.de. July 25, 2008, accessed September 8, 2019 .