No abstract

Candida species are yeasts and within the oral cavity, Candida albicans is the most frequently isolated. There is clear evidence that C. albicans adheres to oral surfaces including acrylic dentures and mucosa. The mechanisms of attachment differ, with candidal adhesion to inert surfaces under the control of hydrophobic and electrostatic forces and adhesion to mucosa dependent on a number of complex ligand-recognition systems. Other factors within the oral environment such as saliva, pH, bacteria and hyphal formation have been shown to influence adhesion of candida species to surfaces in the mouth.

Certaih systemic cenditions and/or defects in tlile irmmume sy,stem may JDt:edisJ!)Qse tliie host to oral candielal infecti0n and tliie commenest ferm of oral 1 cam~ielosis is candida-associatecl tilernture stomatitis.IJntil recently tliier-e has been cemtrev.ersy coneerrniAg 1 t!;le aeti010!iJY of the disease. Althoust:l some ear,lier investigat0rs fimke€l clemture stomatitis witlit trramma or Lflacte~ial infection, 0tt:lers had isolate€! Candida all!Jieams tr.0m the rnewtl;is 0f Ji)atients with tlfle G0Aditi!im. Current stwrnatitis lesiolils ar.e assoeiated witlil tlile cleteetion , ol cal'lli.!il!la species wtiile otlilef factors sueh as dentwre hygiene, trauma, systemic diseases amCil aefi11:ierneies of tfrle immwne s.ysfem may l:>e imvolveeLKe¥ words: Caf'ldida a/J:Jieans, acute pseudemembranous canei~esls. aeete atrepbie camdidosis, eamdit'.la leuk0plakia, cant'.li~a-assoeiated denture stomatftf&, angular cheilitis.

Two-dimensional gel electrophoretic analysis of the proteome of Streptococcus mutans grown at a steady state in a glucose-limited anaerobic continuous culture revealed a number of proteins that were differentially expressed when the growth pH was lowered from pH 7?0 to pH 5?0. Changes in the expression of metabolic proteins were generally limited to three biochemical pathways: glycolysis, alternative acid production and branched-chain amino acid biosynthesis. The relative level of expression of protein spots representing all of the enzymes associated with the Embden-Meyerhof-Parnas pathway, and all but one of the enzymes involved in the major alternative acid fermentation pathways of S. mutans, was identified and measured. Proteome data, in conjunction with end-product and cell-yield analyses, were consistent with a phenotypic change that allowed S. mutans to proliferate at low pH by expending energy to extrude excess H + from the cell, while minimizing the detrimental effects that result from the uncoupling of carbon flux from catabolism and the consequent imbalance in NADH and pyruvate production. The changes in enzyme levels were consistent with a reduction in the formation of the strongest acid, formic acid, which was a consequence of the diversion of pyruvate to both lactate and branched-chain amino acid production when S. mutans was cultivated in an acidic environment.