Barros Letizia M, Boriollo Marcelo F G, Alves Ana Cláudia B A, Klein Marlise I, Gonçalves Reginaldo B, Höfling José F
Clinical Periodontology, Dental School of University of Alfenas, Minas Gerais, Brazil.
Arch Oral Biol. 2008 Dec;53(12):1172-8. doi: 10.1016/j.archoralbio.2008.06.003. Epub 2008 Jul 30.
Mucosal surfaces are the primary oral reservoirs of Candida species, but these species can also be found in subgingival biofilm. The present study investigated the genetic diversity and production of exoenzymes of C. albicans and C. dubliniensis isolated from the oral cavity of systemically healthy patients with periodontitis.
Fifty-three patients were analysed. Samples were collected from three oral cavity sites (periodontal pocket, gingival sulci and oral mucosa), plated and, after isolation, suspect strains of C. albicans and C. dubliniensis were identified by PCR. The genetic diversity of the isolates was evaluated by RAPD and the activities of the secreted aspartyl proteinases and phospholipases were evaluated by the agar plate method.
Twenty-one patients showed positive results for Candida spp. There were no statistically significant differences between genders, or between sites. C. albicans was the most frequently found specie, while C. dubliniensis was isolated from the periodontal pocket of only one patient. Sixteen genotypes were detected among the C. albicans isolates, and one among the C. dubliniensis isolates. The similarity coefficient (S(SM)) values among the C. albicans genotypes ranged from 0.684 to 1.0 with an average of 0.905+/-0.074. All isolates produced high levels of Saps and most of them produced high levels of phospholipases. No relationship was found between the genotypes and the pattern of enzymatic production. There was no association between specific genotypes and their site of isolation.
The results of the present study suggest that genetically homogeneous strains of C. albicans are present in the oral cavity of patients with periodontitis and that these strains are capable of producing high levels of exoenzyme.
黏膜表面是念珠菌属在口腔中的主要储存部位，但这些菌种也可在龈下生物膜中发现。本研究调查了从患有牙周炎的全身健康患者口腔中分离出的白色念珠菌和都柏林念珠菌的遗传多样性及胞外酶产生情况。
对53名患者进行分析。从三个口腔部位（牙周袋、龈沟和口腔黏膜）采集样本，接种培养，分离后通过PCR鉴定疑似白色念珠菌和都柏林念珠菌菌株。通过随机扩增多态性DNA（RAPD）评估分离株的遗传多样性，通过琼脂平板法评估分泌天冬氨酸蛋白酶和磷脂酶的活性。
21名患者念珠菌属检测呈阳性。性别之间或部位之间无统计学显著差异。白色念珠菌是最常发现的菌种，而都柏林念珠菌仅从一名患者的牙周袋中分离出。在白色念珠菌分离株中检测到16种基因型，在都柏林念珠菌分离株中检测到1种基因型。白色念珠菌基因型之间的相似系数（S(SM)）值范围为0.684至1.0，平均为0.905±0.074。所有分离株均产生高水平的天冬氨酸蛋白酶，且大多数产生高水平的磷脂酶。未发现基因型与酶产生模式之间的关系。特定基因型与其分离部位之间无关联。
本研究结果表明，患有牙周炎的患者口腔中存在基因同质的白色念珠菌菌株，且这些菌株能够产生高水平的胞外酶。
