Neisseria Mucosa Does Not Inhibit the Growth of Neisseria gonorrhoeae

Antibiotic-sparing treatments are required to prevent the further emergence of anti-microbial resistance in Neisseria gonorrhoeae. Commensal Neisseria species have previously been found to inhibit the growth of pathogenic Neisseria species. For example, a previous study found that 3 out of 5 historical isolates of Neisseria mucosa could inhibit the growth of N. gonorrhoeae. In this study, we used agar overlay assays to assess if 24 circulating and historical isolates of Neisseria mucosa could inhibit the growth of 28 circulating and historical isolates of N. gonorrhoeae. Although pitting around each colony of N. mucosa created an optical illusion of decreased growth of N. gonorrhoeae, we found no evidence of inhibition (n=24). In contrast, positive controls of Streptococcus pneumoniae and Escherichia coli demonstrated a strong inhibitory effect against the growth of N. gonorrhoeae.

Circulating Isolates of Neisseria mucosa do not Inhibit the Growth of Neisseria gonorrhoeae

We used agar overlay assays to assess if 24 circulating and historical isolates of Neisseria mucosa could inhibit the growth of 28 circulating and historical isolates of N. gonorrhoeae. We found no evidence of inhibition by N. mucosa (n=24). Positive controls Streptococcus pneumoniae and Escherichia coli demonstrated a strong inhibitory effect against the growth of N. gonorrhoeae.

Draft Genome Sequence of Neisseria mucosa Strain HSUH001, Isolated from an Aggressive Periodontal Lesion

ABSTRACT We report the draft genome sequence (143 contigs, with a total length of 2,424,805 bp and an N50 value of 36,066 bp) of a bacterium isolated from an aggressive periodontal lesion in a patient. We assigned strain HSUH001 to Neisseria mucosa through a multilocus sequence analysis.

The Human Microbiome as a Focus of Antibiotic Discovery: Neisseria mucosa Displays Activity Against Neisseria gonorrhoeae

Neisseria gonorrhoeae infections are a serious global health problem. This organism has developed disturbing levels of antibiotic resistance, resulting in the need for new approaches to prevent and treat gonorrhea. The genus Neisseria also includes several members of the human microbiome that live in close association with an array of microbial partners in a variety of niches. We designed an undergraduate antibiotic discovery project to examine a panel of nonpathogenic Neisseria species for their ability to produce antimicrobial secondary metabolites. Five strains belonging to the N. mucosa species group displayed activity against other Neisseria in delayed antagonism assays; three of these were active against N. gonorrhoeae. The antimicrobial compound secreted by N. mucosa NRL 9300 remained active in the presence of catalase, trypsin, and HEPES buffer, and effectively inhibited a DNA uptake mutant of N. gonorrhoeae. Antimicrobial activity was also retained in an ethyl acetate extract of plate grown N. mucosa NRL 9300. These data suggest N. mucosa produces an antimicrobial secondary metabolite that is distinct from previously described antigonococcal agents. This work also serves as a demonstration project that could easily be adapted to studying other members of the human microbiome in undergraduate settings. We offer the perspective that both introductory and more advanced course-based and apprentice-style antibiotic discovery projects focused on the microbiome have the potential to enrich undergraduate curricula and we describe transferrable techniques and strategies to facilitate project design.

Characterization of Oral Microbiome and Exploration of Potential Biomarkers in Patients with Pancreatic Cancer

Pancreatic cancer (PC) is highly malignant and lacks an effective therapeutic schedule, hence that early diagnosis is of great importance to achieve a good prognosis. Oral bacteria have been proved to be associated with pancreatic cancer, but the specific mechanism has not been comprehensively illustrated. In our study, thirty-seven saliva samples in total were collected with ten from PC patients, seventeen from benign pancreatic disease (BPD) patients, and ten from healthy controls (HC). The oral bacterial community of HC, PC, and BPD groups was profiled by 16S rDNA high-throughput sequencing and bioinformatic methods. As shown by Simpson, Inverse Simpson, Shannon and Heip, oral microbiome diversity of HC, BPD and PC groups is in increasing order with the BPD and PC groups significantly higher than the HC group. Principal coordinate analysis (PCoA) suggested that grouping by PC, BPD and HC was statistically significant. The linear discriminant analysis effect size (LEfSe) identified high concentrations of Fusobacterium periodonticum and low concentrations of Neisseria mucosa as specific risk factors for PC. Furthermore, predicted functions showed changes such as RNA processing and modification as well as the pathway of NOD-like receptor signaling occurred in both PC and HC groups. Conclusively, our findings have confirmed the destruction of oral bacterial community balance among patients with PC and BPD and indicated the potential of Fusobacterium periodonticum and Neisseria mucosa as diagnostic biomarkers of PC.

Response of Intestinal Mucosal Microbiota in Diarrheal Mice to Ge-gen-qin-lian Decoction

Background: Ge-gen-qin-lian Decoction (GD) has been extensively used for the treatment of diarrhea with intestinal dampness heat syndrome(IDHS) with a satisfying therapeutic effect. However, the active ingredients and mechanism of GD against diarrhea with IDHS have not been fully elucidated. The occurrence of diarrhea is closely related to the intestinal flora, and the compound of Traditional Chinese Medicine(TCM) can exert its curative effect by regulating the intestinal flora, and exploring the relationship between the two is conducive to the clarification of pharmacology. Results: Animal experiments indicted that the OTU number and Alpha diversity index in the intestinal mucosa flora of the treatment group(cttm) recovered and higher than that of the control group(ctcm). PCoA results showed that there were differences in the community structure between the Con and GD. At the species level, the abundance of Lactobacillus crispatus and Muribaculum intestinal in the model group(ctmm) decreased, and the Neisseria mucosa increased (p<0.05). After being treated with GD, Muribaculum intestinal increased, and Lactobacillus curlyus and Neisseria mucosa decreased (p<0.05). Combined with network pharmacology analysis, we screened out 146 active ingredients in GD corresponding to 252 component targets, and 328 disease targets in diarrhea to obtain 31 drug-disease common targets. The key targets involved TNF, IL-6, EFGR etc. KEGG pathway enrichment resulted in HIF-1 signaling pathway, VEGFA signaling pathway, Adipocytokine signaling pathway and so on (p<0.05). Conclusions: GD could restore the diversity and abundance of intestinal mucosa in diarrheal mice with IDHS, promote the abundance of Muribaculum intestinal, inhibit the abundance of Neisseria mucosa. Through the characteristic of multiple targets and multiple channels, the active ingredients of GD intervened from oxidative stress and inflammatory response to adjust the balance of intestinal mucosa flora, thereby playing the role of treating diarrhea.

Evaluation of the Microbiological Profile of Alveolar Residual Screws and Cleft-Adjacent Teeth in Individuals With Complete Unilateral Fissures

Objective: To evaluate the microbiota profile of residual alveolar slits and teeth adjacent to the cleft in fissured individuals. Designs: This study used a cross-sectional design. Participants: Twenty individuals, aged 14 to 24 years, who had a residual fissure in the maxillary alveolar ridge region were selected. Main outcome measures: Three sites per individual were selected for microbiological collection (the site of the residual cleft and the 2 nearest teeth). The samples were analyzed using the Checkerboard DNA–DNA hybridization technique for 73 species of bacteria. Results: All the species analyzed were found in the 2 niches (slits and teeth). The bacterial species present in the largest number in the residual cracks were Prevotella melaninogenica, Prevotella nigrescens, and Streptococcus mitis. With regard to the bacterial profiles in the mesial and distal faces, the most prevalent species were P nigrescens, Veillonella parvula, and Fusobacterium nucleatum sp vicentii. The analysis of all the collected samples demonstrated very similar profiles for the mesial and distal faces, with these 2 sites even presenting the same species in greater frequencies. Higher counts of 20 bacterial species (Wilcoxon test) were observed in the dental niche, in relation to the fissure, particularly, P nigrescens, V parvula, F nucleatum sp vicentii, and Neisseria mucosa. Conclusion: Some species were significantly more prevalent in the residual alveolar fissures and in adjacent teeth. The comparison between the profiles of the 2 niches demonstrated large differences in the most frequent species in the teeth, and no qualitative differences with regard to specific pathogens.

Persistence Dynamics of Antimicrobial-Resistant Neisseria in the Pharynx of Rhesus Macaques

ABSTRACT Pharyngeal infections by Neisseria gonorrhoeae are often asymptomatic, making them difficult to treat. However, in vivo animal modeling of human pharyngeal infections by pathogenic Neisseria species is challenging due to numerous host tropism barriers. We have relied on rhesus macaques to investigate pharyngeal persistence of naturally occurring Neisseria species in response to antibiotics. These species include Neisseria mucosa, Neisseria oralis, and a species unique to macaques. Four animals previously treated intramuscularly with the fluoroquinolone enrofloxacin for 2 weeks were monitored for persistence of their preexisting Neisseria populations for a period of 10 weeks. Enrofloxacin exposure did not eliminate preexisting flora from two of the four animals. Characterization of a collection of macaque Neisseria isolates supported the hypothesis that pharyngeal persistence was linked to reduced enrofloxacin susceptibility conferred by mutations in either gyrA or parC. Interestingly, we observed a change in neisserial population dynamics for several weeks following enrofloxacin exposure. Enrofloxacin appeared to promote competition between strains for dominance in the pharyngeal niche. Specifically, following enrofloxacin treatment, strains bearing single gyrA mutations and low MICs persisted long-term. In contrast, strains with both gyrA and parC mutations and high MICs became culturally undetectable, consistent with the hypothesis that they were less fit. Our study has provided insight into pharyngeal persistence dynamics of Neisseria species bearing fluoroquinolone resistance determinants. The rhesus macaque provides a valuable host animal that may be used in the future to simulate treatment failures associated with the presence of antimicrobial-resistant Neisseria spp. in the human pharynx.