Effects of different acidulants on growth of 'Streptococcus milleri group' strains isolated from various sites of the human body

Growth of human clinical isolates of Streptococcus constellatus, Strep. intermedius and Strep. anginosus in HCl-, acetate and lactate acidified media was investigated. Under aerobic conditions, Strep. constellatus and Strep. anginosus were significantly more tolerant to all the acidulants than was Strep. intermedius. Under anaerobic conditions, Strep. anginosus and Strep. intermedius were significantly more tolerant to acetic acid (pH < 4.5) than Strep. constellatus     

Salivary immunoglobulin classes in Nigerian smokers with periodontitis

AIM:To determine the levels of salivary immunoglobulin classes in Nigerian smokers and non-smokers with periodontitis.METHODS:Sixty-nine individuals were recruited into this study after obtaining informed consent.They were subdivided into three groups that consisted of 20(aged 46 ± 11 years) cigarette smokers with periodontitis(S+P);24(40 ± 12 years) smokers without periodontitis(S-P);and 25(53 ± 11 years) non-smokers with periodontitis(NS+P).An oral and maxillofacial surgeon used radiographs for periodontal probing for the diagnosis of periodontitis.The smokers included subjects who smoked at least six cigarettes per day and all the periodontitis patients were newly diagnosed.About 5 mL of unstimulated saliva was expectorated by each subject into plain sample bottles.Salivary immunoglobulin levels were estimated using enzyme linked immunosorbent assay.Student's t test was used to deter-mine significant differences between the means.Values of P 0.05 were regarded as significant.RESULTS:No significant differences were observed in the mean salivary levels of the immunoglobulin classes(IgG,IgA,IgM and IgE) when S+P was compared with S-P.Mean salivary levels of IgA(520.0 ± 155.1 ng/mL vs 670.0 ± 110 ng/mL,P = 0.000) and IgM(644.5 ± 160.0 ng/mL vs 791.4 ± 43.7 ng/mL,P = 0.000) were significantly lower in the S+P compared with NS+P group.Salivary IgA(570.4 ± 145.6 ng/mL vs 670.0 ± 110 ng/mL,P = 0.008) and IgM(703.1 ± 169.3 ng/mL vs 791.4 ± 43.7 ng/mL,P = 0.012) levels were significantly lower in the S-P compared with NS+P group.Only one(5%) periodontal patient had detectable levels of salivary IgE(0.20 IU/mL).Similarly,only one smoker(4.17%) had detectable levels of salivary IgE(0.04 IU/mL) and two non-smokers(9.52%) had detectable levels of IgE(0.24 IU/mL).CONCLUSION:Our study suggests that reduced salivary IgA and IgM levels in smokers with periodontitis could enhance increased susceptibility to periodontitis.     

Streptococci species of anginosus group isolated from oral and maxillofacial infections

The aim of the study was to isolate and identify at species level streptococci strains of anginosus group in pus samples collected from 110 patients with oral and maxillofacial (OMF) infections. Gram-stained smears and cultures on selective and nonselective media were done from each of the 111 pus samples (2 samples were collected from one of the patients, who presented 2 oral abscesses at the same time). The isolates were identified on the basis of cultural and biochemical characteristics. Speciation of the anginosus group isolates was performed using the Rapid ID 32 Strep system (Bio Mérieux, France). Fourty-four anginosus group strains were isolated from 42 patients. Fourty of these isolates were identified as Streptococcus anginosus (2 nonidentical isolates were found in 2 patients), 3 isolates as Streptococcus constellatus and only one as Streptococcus intermedius. The study confirmed that the anginosus group is often involved in OMF infections alone or in association with other aerobic and/or anaerobic bacteria. In the investigated cases, Streptococcus anginosus was by far the most frequently isolated species within the anginosus group.     

Nested PCR for detection of mutans streptococci in dental plaque

AIMS: Mutans streptococci such as Streptococcus mutans and Streptococcus sobrinus have been implicated in human dental caries. In an attempt to develop a rapid and sensitive method for detecting Strep. mutans and Strep. sobrinus in dental plaque, a nested PCR amplification based on the 16S rRNA gene was employed. METHODS AND RESULTS: A universal set of PCR primers for bacterial 16S rRNA gene was introduced for the first PCR, and then two sets of primers specific for the 16S rRNA gene sequences of either Strep. mutans or Strep. sobrinus were used for the second PCR. Eighteen plaque samples were analyzed, and a nested PCR was shown to be more sensitive for detecting Strep. mutans and Strep. sobrinus than direct PCR. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: The 16S rRNA gene-based nested PCR method is a rapid and sensitive method for the detection of mutans streptococci, and may also be suitable for carrying out large-scale studies on the cariogenicity of mutans streptococci.     

中、重度牙周炎与冠心病患者白细胞介素17 及血脂水平的比较

目的:研究汉族人群中、重度牙周炎与冠心病的相关性并初步探讨白细胞介素17在二者相关性中的可能作用。方法:检测和分析40名健康者(健康组)、40例中、重度牙周炎患者(牙周炎组)、28例冠状动脉粥样硬化性心脏病患者(冠心病组)及47例患冠心病伴中、重度牙周炎的患者(冠心病+牙周炎组)血清白细胞介素17水平、血脂水平(血清低密度脂蛋白、高密度脂蛋白、胆固醇、总胆固醇和甘油三酯)和牙周临床指数(附着丧失、探诊深度和探诊出血)。结果:单因素方差分析结果显示,健康组、牙周炎组、冠心病组及牙周炎+冠心病组的血清白细胞介素17水平分别为(13.01±1.23)、(24.45±2.13)、(59.90±2.23)和(68.87±3.43)ng/L,各组血清白细胞介素17间的差异具有统计学意义(P<0.05),且经协方差分析校正年龄、受教育状况、血压和体重指数后显示,各组血清白细胞介素17水平间的差异仍具有统计学意义(P<0.05)。多元Logistic回归分析结果显示,中、重度牙周炎患者发生冠心病的可能性高于牙周健康者,其发生冠心病的相对风险率比值比为2.416(P=0.039;95%CI:1.126-6.659)。经协方差分析校正年龄、受教育状况、血压和体重指数后,各组血清总胆固醇水平间差异仍具有统计学意义(P=0.018)。结论:严重的牙周感染可能通过改变白细胞介素17水平,影响全身炎症反应和冠心病的发生及发展,可能是冠心病事件的危险因素之一。     

Identification of Streptococcus salivarius by PCR and DNA probe

AIMS: To establish species-specific PCR and DNA probe methods for Streptococcus salivarius and to clarify the distribution of dextranase in oral isolates of Strep. salivarius. METHODS AND RESULTS: A pair of PCR primers and a DNA probe were designed based on the nucleotide sequence of the dextranase gene of Strep. salivarius JCM5707. Both the PCR primer and the DNA probe specifically detected Strep. salivarius but none of the other oral streptococci (23 strains of 13 species). The primer and the probe were capable of detecting 1 pg and 1 ng of the genomic DNA, respectively, purified from Strep. salivarius JCM5707. All oral isolates (130 strains from 12 subjects) of Strep. salivarius from human saliva were positive by both methods. CONCLUSION: The present PCR and DNA probe methods are highly specific to Strep. salivarius and are useful for the its detection and identification of this bacterium. The dextranase widely distributes among oral isolates of Strep. salivarius. Significance and Impact of the Study: The DNA sequence of a dextranase gene present in the genome of Strep. salivarius is useful as the target DNA of the species-specific PCR and DNA probe.     

Comparison of the oral bacterial flora in saliva from a healthy subject and two periodontitis patients by sequence analysis of 16S rDNA libraries

The oral bacterial flora in the saliva from two patients with periodontitis and from a periodontally healthy subject were compared using a sequence analysis of 16S rDNA libraries without cultivation. 16S rDNAs were amplified from salivary DNA by PCR and cloned. Randomly selected clones were partially sequenced. On the basis of sequence similarities, the clones were classified into several clusters corresponding to the major phylum of the domain Bacteria. The major phylum in the libraries was the low G+C Gram-positive bacteria. There was no clonal sequence affiliated with periodontopathic bacteria in the salivary sample from the healthy subject, while a number of periodontal pathogens such as Campylobacter rectus, Prevotella intermedia, Porphyromonas gingivalis and Treponema socranskii were detected in the salivary samples from the patients with periodontitis. In addition, a number of previously uncharacterized and uncultured microorganisms were recognized. These organisms may have some role in periodontal disease. This study reveals some potential for a molecular-biological technique to analyze the oral microflora associated with periodontal disease, including previously uncharacterized and uncultured microorganisms, without cultivation.     

Detection of Dialister pneumosintes in the subgingival biofilm of subjects with periodontal disease

Dialister pneumosintes has been indicated as a potentially new periodontopathic species. This study evaluated the prevalence of this microorganism in saliva and subgingival biofilm from subjects with different periodontal conditions. Subgingival biofilm and saliva samples from 48 subjects with periodontal health (PH) and 116 patients with chronic periodontitis (CP) were obtained. DNA was extracted from the samples and the presence of D. pneumosintes was determined by PCR. Differences in clinical parameters and frequency of D. pneumosintes between groups were sought by Mann-Whitney, Chi-square and Fisher's exact tests. Overall, D. pneumosintes was detected in 47.8% of the biofilm samples, but only in 3% of saliva samples. CP patients presented a significantly greater mean prevalence of this species in sites with periodontal health and periodontal infection (43.5+/-7.4% and 62.1+/-6.4%, respectively) than PH subjects (29.4+/-7.9%) (Mann-Whitney; p<0.01). Moreover, significant associations between the prevalence of D. pneumosintes and pocket depth (p=0.001), attachment loss (p=0.001) and bleeding on probing (GLM, p=0.014) were observed after adjusting for age and gender. These findings corroborate the association of D. pneumosintes with periodontitis.     

牙周夹板联合正畸治疗对牙周炎所致前牙扇形移位患者咀嚼功能和龈沟液PGE2、sICAM-1、PAK5的影响

目的:探讨牙周夹板联合正畸治疗对牙周炎所致前牙扇形移位患者咀嚼功能和龈沟液中前列素E2(PGE2)、可溶性细胞间黏附分子-1(s ICAM-1)、p2l活化激酶5(PAK5)的影响。方法:采用随机数字表法,将我院2018年2月~2020年2月间接收的93例牙周炎所致前牙扇形移位患者分为对照组(46例,牙周基础治疗、牙周夹板治疗)和研究组(47例,牙周基础治疗、牙周夹板治疗联合正畸治疗),观察两组疗效,对比两组治疗前后的牙周情况,咀嚼功能、美观度,龈沟液PGE2、s ICAM-1、PAK5水平。结果:研究组的临床总有效率高于对照组(P<0.05)。研究组治疗后牙周菌斑指数(PLI)、探诊深度(PD)、牙龈指数(GI)、附着丧失(AL)、龈沟出血指数(SBI)低于对照组(P<0.05)。研究组治疗后探诊出血率、前牙咬合低于对照组,咀嚼功能评分高于对照组(P<0.05)。研究组治疗后牙周袋深度、前牙覆盖度、牙槽骨高度低于对照组(P<0.05)。研究组治疗后龈沟液PGE2、s ICAM-1、PAK5水平低于对照组(P<0.05)。结论:牙周夹板联合正畸治疗可有效恢复牙周炎所致前牙扇形移位患者牙周功能和咀嚼功能,且美观效果好,还可减轻对龈沟液PGE2、s ICAM-1、PAK5水平的影响。     

牙龈卟啉单胞菌、嵴链球菌、口腔链球菌属在口腔内不同解剖部位的分布

目的探讨牙龈卟啉单胞菌(Porphyromonas gingivalis)、嵴链球菌(Streptococcus cristatus)、口腔链球菌属(Streptococci oralis)在慢性牙周炎患者及牙周健康者不同口腔解剖部位生物膜的分布情况。方法选取慢性牙周炎患者25例,牙周健康者24例,分别作为慢性牙周炎组及健康对照组。测量临床指标(探诊深度、附着丧失和探诊出血),取受试者龈下菌斑、舌背、颊黏膜和唾液样品。Real-time PCR分析受试者不同受检部位S.cristatus、P.gingivalis、Streptococci oralis相对数量。结果慢性牙周炎组四个受检部位中P.gingivalis数量均大于健康对照组;慢性牙周炎组龈下菌斑中P.gingivalis数量大于其余受检部位;而慢性牙周炎组龈下菌斑、舌背、颊黏膜三个受检部位S.cristatus、Streptococci oralis数量小于健康对照者。结论与牙周健康者比较,慢性牙周炎患者口腔内不同解剖位置P.gingivalis数量增多,S.cristatus、Streptococci oralis数量减少;P.gingivalis检出数量增加提示牙周炎患病风险增加,而S.cristatus、Streptococci oralis检出数量降低提示牙周炎患病风险降低。     

Salivary levels of inflammatory cytokines and their association to periodontal disease in systemic lupus erythematosus patients. A case-control study

Both Systemic Lupus Erythematosus (SLE) and periodontal disease (PD) present a similar immunological profile mainly characterized by altered cytokine levels. In this study we sought to investigate the salivary levels of inflammatory cytokines and their association with PD in SLE patients. 60 patients with SLE and 54 systemically healthy individuals underwent a full periodontal clinical examination. They were then grouped according to their periodontal status. Stimulated saliva was collected in order to evaluate the salivary levels of interferon (IFN-γ), Interleukin (IL)-10, IL-17, IL-1β, and IL-4. Systemically healthy individuals with periodontitis (group P) presented higher levels of cytokines when compared to systemically healthy individuals, with no periodontal disease (group S) (p < 0.05). Additionally, in the P group, patients presented similar levels of cytokines to those of the patients with SLE, regardless of the presence of PD (p > 0.05), for most of the analyzed cytokines. There was a positive correlation in SLE patients, including IL-1β and all periodontal clinical parameters (p < 0.05), and between IL-4 and gingival bleeding index and the presence of biofilm (p < 0.05). Thus, our results confirmed, that patients with PD showed higher salivary levels of cytokines and, in SLE patients, the increased levels of salivary cytokines were observed even in the absence of periodontitis. IL-1β and IL-4 salivary levels were also positively correlated with periodontal status indicating their potential as markers of the amount and extent of periodontal damage in patients with SLE.     

Genetic diversity in Swiss cheese starter cultures assessed by pulsed field gel electrophoresis and arbitrarily primed PCR

AIMS: To assess intraspecific genetic heterogeneity among commercial Swiss cheese starter culture strains of Lactobacillus helveticus, Streptococcus thermophilus and Propionibacterium freudenreichii and to compare the efficacy of two genetic typing methods. METHODS AND RESULTS: Two genetic typing methods, pulsed field gel electrophoresis (PFGE) and arbitrarily primed PCR (AP-PCR), were used. Nine Strep. thermophilus strains revealed eight PFGE and five AP-PCR genotypes. Seventeen Lactobacillus strains yielded 16 and five genotypes by PFGE and AP-PCR, respectively. Eleven Propionibacterium strains yielded 10 PFGE genotypes. Cluster analysis of PFGE profiles generated similarity coefficients for Strep. thermophilus, Lact. helveticus and Prop. freudenreichii strains of 29.5%, 60.3%, and 30.5%, respectively. Milk acidification rates for Strep. thermophilus and Lact. helveticus were determined. CONCLUSIONS: Pulsed field gel electrophoresis is more discriminatory than AP-PCR. The Lact. helveticus group is more homogeneous than the other species examined. Strains with > 87% similarity by PFGE consistently had the same acidification rate and AP-PCR profile. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial strains sold for Swiss cheese manufacture in the United States are genetically diverse. Clustering of genetically related bacteria may be useful in identifying new strains with industrially relevant traits.     

Identification of the anginosus group within the genus Streptococcus using polymerase chain reaction

The aim of this study was to establish an identification method for the anginosus group within the genus Streptococcus by polymerase chain reaction (PCR). Using a primer pair based on the group-specific sequences of penicillin-binding protein 2B (pbp2b) gene, a 275-bp fragment was amplified from each species in the group but no size-matched products were obtained in other streptococci. Further identification in the species or subspecies level was possible by a multiplex PCR with primers for the 16S ribosomal RNA gene of Streptococcus anginosus, the hyaluronate lyase genes both of Streptococcus intermedius and Streptococcus constellatus subsp. constellatus, and the intermedilysin (ily) gene of S. intermedius. In the case ofStreptococcus constellatus subsp. pharyngis, the amplified fragment from the S. intermedius-type hyaluronate lyase gene was obtained, while that from the ily gene was not. These results also indicate that two different hyaluronate lyase genes are distributed among the anginosus group.     

牙龈卟啉单胞菌感染对慢性牙周炎患者牙周指标、NLRP-3炎性小体通路和Th17/Treg细胞平衡的影响

摘要 目的：探讨牙龈卟啉单胞菌（PG）感染对慢性牙周炎（CP）患者牙周指标、Nod样受体蛋白-3（NLRP-3）炎性小体通路和辅助性T细胞17（Th17）/调节性T细胞（Treg）平衡的影响。方法：选择2018年6月至2021年11月在本院进行拔牙治疗的慢性牙周炎患者106例为CP组,根据是否感染PG分为感染组和未感染组;另选择因阻生齿、错位牙在本院进行治疗的牙周健康患者63例为对照组。记录所有对象的探诊深度（PD）、菌斑指数（PLI）、出血指数（BI）、附着丧失（AL）,采用聚合酶链式反应（PCR）技术检测PG感染率,采用RT-PCR技术检测牙周膜组织中NLRP-3 mRNA,接头蛋白凋亡相关斑点样蛋白（ASC） mRNA、半胱氨酸天冬氨酸酶-1（Caspase-1） mRNA的表达量,采用FACSCalibur流式细胞仪检测外周血Th17、Terg 水平并计算Th17/Treg,比较两组各检测指标水平。结果：对照组PG感染阳性率为17.46%,低于CP组的79.25%,两组比较差异有统计学意义（P＜0.05）。感染组PD、PLI、BI、AL水平均高于非感染组,差异有统计学意义（P＜0.05）。感染组NLRP-3 mRNA、ASC mRNA、Caspase-1 mRNA表达量均高于非感染组,差异有统计学意义（P＜0.05）。感染组外周血Th17细胞、Th17/Treg水平高于非感染组,Treg水平低于非感染组,差异有统计学意义（P＜0.05）。结论：CP患者多数存在PG感染,PG感染对患者的牙周健康、炎症及免疫有明显的影响。     

Preliminary assessment of safety and effectiveness in humans of ProBiora3 ™, a probiotic mouthwash

Aims:  To conduct a pilot human clinical trial to assess the safety and to test the ability of a probiotic mouthwash, ProBiora³, to affect the levels of Streptococcus mutans and certain known periodontal pathogens in the mouth when administered twice daily over a period of 4 weeks.
Methods and Results:  The mouthwash contained three specific strains of naturally occurring oral bacteria and was tested at two dose levels: 10⁶ and 10⁸ colony forming units each of Strep. oralis strain KJ3sm, Strep. uberis strain KJ2sm, and the spontaneous lactic acid-deficient variant of Strep. rattus , strain JH145. Substantial decreases in the levels of the marker bacteria were observed. No safety issues were noted with the twice daily application of this mouthwash.
Conclusions:  Despite the small number of subjects and the use of young, orally healthy adults, along with the inherent variability in the microbiological measurements, the probiotic mouthwash was able to substantially affect the levels of dental pathogens in saliva and periodontal pathogens in subgingival plaque.
Significance and Impact of the Study:  The results of this pilot human study suggest that the probiotic mouthwash product may be safe for daily use as an aid in maintaining both dental and periodontal health.     

侵袭性牙周炎伴错牙合畸形患者牙周-正畸联合治疗前后血清SAA、leptin的变化及与牙周指标和辅助性T细胞亚群的相关性分析

摘要 目的：探讨侵袭性牙周炎伴错牙合畸形患者牙周-正畸联合治疗前后血清淀粉样蛋白A（SAA）、瘦素（leptin）的变化及与牙周指标和辅助性T细胞（Th）亚群的相关性。方法：选择2020年6月-2022年8月解放军总医院京中医疗区黄寺门诊部口腔科收治的80例侵袭性牙周炎伴错牙合畸形患者（牙周炎组）和65例于口腔门诊检查的健康志愿者（对照组）。所有患者均接受牙周-正畸联合治疗,治疗前后分别检测血清SAA、leptin水平以及外周血中Th1、Th2、Th17细胞占比,并评估牙周指标变化。Pearson相关性分析血清SAA、leptin水平与牙周指标以及外周血中Th1、Th2、Th17细胞占比的相关性。结果：牙周炎组治疗前血清SAA、leptin水平,外周血Th1、Th17细胞占比,出血指数（SBI）、菌斑指数（PLI）、附着丧失（AL）、牙周探诊深度（PD）高于对照组（P＜0.05）,外周血Th2细胞占比低于对照组（P＜0.05）。牙周炎组治疗后血清SAA、leptin水平,外周血Th1、Th17细胞占比,PLI、SBI、AL、PD较治疗前降低（P＜0.05）,外周血Th2细胞占比较治疗前增高（P＜0.05）。牙周炎组血清SAA、leptin与PLI、SBI、AL、PD,外周血Th1、Th17细胞占比呈正相关,与外周血Th2细胞占比呈负相关（P＜0.05）。结论：侵袭性牙周炎伴错牙合畸形患者血清SAA、leptin水平增高,经牙周-正畸联合治疗后下降,高水平SAA、leptin与牙周组织破坏程度以及Th亚群紊乱有关,检测血清SAA、leptin水平可评估侵袭性牙周炎牙周组织破坏程度以及细胞免疫状态。     

Quantification of Subgingival Bacterial Pathogens at Different Stages of Periodontal Diseases

Anaerobic gram-negative oral bacteria such as Treponema denticola, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Campylobacter rectus, and Fusobacterium nucleatum are closely associated with periodontal diseases. We measured the relative population (bacterial levels) of these oral pathogens in subgingival tissues of patients at different stages of Korean chronic periodontal diseases. We divided the individuals into those with chronic gingivitis (G), moderate periodontitis (P1), severe periodontitis (P2), and normal individuals (N) (n?=?20 for each group) and subgingival tissue samples were collected. We used real-time PCR with TaqMan probes to evaluate the change of periodontal pathogens among different stages of periodontitis. Bacterial levels of A. actinomycetemcomitans and C. rectus are significantly increased in individuals with chronic gingivitis and moderate periodontitis, but unchanged in severe periodontitis patients. These results suggest that analyzing certain bacterial levels among total oral pathogens may facilitate understanding of the role of periodontal bacteria in the early stages of periodontitis.     

PCR直接检测龈下菌斑主要可疑牙周致病菌

目的：应用PCR方法直接检测龈下菌斑主要可疑牙周致病菌与牙周病活动部位的关系,探讨其方法的可行性并探讨其主要可疑牙周致病菌的分布规律。方法：应用聚合酶链反应(polymerase chain reaction,PCR)直接检测龈下菌斑主要可疑致病菌16s RNA保守区域片段。40名受试者包括牙周病患者20人,每人同口取一个牙周病活动部位,一个相对健康或牙周病静止对照部位;成人健康者20人,每人各取一个标本。结果：龈下菌斑5种可疑牙周致病菌在牙周病活动部位的检出率牙龈卟啉菌为86％,福赛类杆菌为95％,螺旋体为86％,中间普氏菌和黑色普氏菌分别为95％和33％,均显著高于同口部位对照组和健康对照组。结论：PCR直接检测菌斑牙龈卟啉单胞菌、中间普氏菌、福赛类杆菌、齿密螺旋体及黑色普氏菌匀与牙周炎活动部位相关。     

Genotypic and phenotypic heterogeneity of Streptococcus thermophilus strains isolated from dairy products

AIMS: Forty strains of Streptococcus thermophilus isolated from dairy products were identified and typed by a polyphasic approach which included phenotypic and genotypic criteria. METHODS AND RESULTS: Strains were identified by sugar fermentation pattern and species-specific PCR. Phenotypic diversity was evaluated by a chemometric model taking into account some biochemical characteristics (e.g. acidifying and peptidase activities) of technological interest. Genotypic diversity was evidenced by PCR fingerprinting. The overall phenotypic and genotypic information was elaborated on a multivariate statistical basis by principal components analysis and cluster analysis, respectively. When acidifying and peptidase activities were considered, PCA indicated that most of the strains isolated from Pecorino Toscano cheese were separable from the others. Similarly, most of the starter culture strains tended to separate from the cheese isolates. CONCLUSIONS: A wide strain heterogeneity among Strep. thermophilus strains isolated from dairy products was observed. SIGNIFICANCE AND IMPACT OF THE STUDY: A computerized analysis of genotypic and phenotypic information could be applied successfully to differentiate and characterize reliably and rapidly isolates occurring in different dairy products and to comprehend the technological role of specific Strep. thermophilus strains in dairy technology.