The bactericidal effects of human salivary histatin 5 on Porphyromonas gingivalis
Date
1994
DOI
Authors
Colon-Deglans, Jose Oscar
Version
OA Version
Citation
Abstract
Previous studies with oral bacterial and fungal pathogens have
demonstrated that histatin 5 is the most potent histatin, a group
of histidine-rich salivary proteins present in parotid secretions
with respect to antibacterial and antifungal effects. The present
study was aimed at investigating the ef feet of human parotid
salivary histatin? on the viability of the periodontal pathogen
Porphyromonas gingivalis (P.g.). Experimentally, the viability of
P.g. was studied after exposure to incremental doses of histatin 5
at different pH values (pH 5.0, 6.0, 7.0 and 8.0). Histatin 5 from
human parotid secretion was isolated by Bio-Gel P-2 chromatography
and reverse-phase high-performance liquid chromatography. The
purity of histatin 5 was determined by polyacrylamide gel
electrophoresis and amino acid analysis.
Following incubation, bacteria were washed by successive
centrifugation, plated onto enriched Trypticase soy agar, and
incubated anaerobically at 37 °C. After 48 hr, colony forming units
were counted. Linear regression analysis was used to evaluate doseresponse.
The most perfect fit for a linear regression was found
for pH 6.0 and 7.0 (p<0.02) with corresponding LD50 values of 0.19
mM and 0.51 mM, respectively.
The data indicate that histatin 5 is bactericidal on P.gingivalis and this effect is modulated by the pH values of the
bacterial environment in contact with histatin 5. The relative
bactericidal potency was higher at pH 5.0 and decreased as pH
increased.
Description
Thesis (M.Sc.D.)--Boston University, Henry M. Goldman School of Graduate Dentistry, 1994 (Oral Biology).
Includes bibliographical references (leaves 57-84).
Includes bibliographical references (leaves 57-84).
License
This work is being made available in OpenBU by permission of its author, and is available for research purposes only. All rights are reserved to the author.