Dynamic changes of total acid and bacterial communities during the traditional fermentation of Hong Qu glutinous rice wine

Background: Hong Qu glutinous rice wine (HQGRW) is brewed under non-aseptic fermentation conditions, so it usually has a relatively high total acid content. The aim of this study was to investigate the dynamics of the bacterial communities and total acid during the fermentation of HQGRW and elucidate the correlation between total acid and bacterial communities. Results: The results showed that the period of rapid acid increase during fermentation occurred at the early stage of fermentation. There was a negative response between total acid increase and the rate of increase in alcohol during the early fermentation stage. Bacterial community analysis using high-throughput sequencing technology was found that the dominant bacterial communities changed during the traditional fermentation of HQGRW. Both principal component analysis (PCA) and hierarchical clustering analysis revealed that there was a great difference between the bacterial communities of Hong Qu starter and those identified during the fermentation process. Furthermore, the key bacteria likely to be associated with total acid were identified by Spearman's correlation analysis. Lactobacillus, unclassified Lactobacillaceae, and Pediococcus were found, which can make significant contributions to the total acid development (| r| N 0.6 with FDR adjusted P b 0.05), establishing that these bacteria can associate closely with the total acid of rice wine. Conclusions: This was the first study to investigate the correlation between bacterial communities and total acid during the fermentation of HQGRW. These findings may be helpful in the development of a set of fermentation techniques for controlling total acid.

Early bacterial biofilm colonizers in the coastal waters of Mauritius

Background: The past years have witnessed a growing number of researches in biofilm forming communities due to their environmental and maritime industrial implications. To gain a better understanding of the early bacterial biofilm community, microfiber nets were used as artificial substrates and incubated for a period of 24 h in Mauritian coastal waters. Next-generation sequencing technologies were employed as a tool for identification of early bacterial communities. Different genes associated with quorum sensing and cell motility were further investigated. Results: Proteobacteria were identified as the predominant bacterial microorganisms in the biofilm within the 24 h incubation, of which members affiliated to Gammaproteobacteria, Alphaproteobacteria and Betaproteobacteria were among the most abundant classes. The biofilm community patterns were also driven by phyla such as Firmicutes, Bacteroidetes, Chloroflexi, Actinobacteria and Verrucomicrobia. The functional analysis based on KEGG classification indicated high activities in carbohydrate, lipid and amino acids metabolism. Different genes encoding for luxI, lasI, agrC, flhA, cheA and cheB showed the involvement of microbial members in quorum sensing and cell motility. Conclusion: This study provides both an insight on the early bacterial biofilm forming community and the genes involved in quorum sensing and bacterial cell motility.

Silkworm excrement bacterial communities diversity in different instars based on 16S rDNA sequence analysis / 中国中药杂志

This paper investigated the diversity of the silkworm excrement bacterial communities in different ages before and after drying, aiming to clarify the differences of bacterial communities in composition and bacterial abundance and the influences of drying treatment, and provide scientific basis for the efficacy of scientific connotation and utilization of silkworm excrement. High-throughput sequencing technique was used to measure the sequence of 16S rDNA-V4 variable region of bacteria in silkworm excrement. QIIME, Mothur and PICRUSt software programs were employed to sort and calculate the number of sequences and operational taxonomic units (OTUs) for each sample. Thereafter, the abundance, distribution, alpha diversity index of species, beta diversity and bacterial communities diversity among different sample groups and predicted the bacterial gene functions were analyzed. In this study, the numbers of effective sequences for six samples were 259 250; the rarefaction curves showed a sufficient sequencing depth, and the number of OTUs was close to saturation. The bacteria in silkworm excrement belonged to the following five phylums: Proteobacteria (89.3%), Actinobacteria (5.0%), Firmicutes (4.4%), Bacteroidetes (1.1%) and Cyanobacteria (0.2%). The dominant specie was Cyanobacteria of the total bacteria identified, respectively. The abundances and diversities of the silkworm excrement bacterial communities have been reduced after drying treatment, especially the silkworm excrement of the fifth instar. PICRUSt analysis was performed to show that abundance of the functional genes such as membrane transport, carbohydrate metabolism, amino acid metabolism, lipid metabolism, nucleotide metabolism, cellular processes and signaling were relatively high. The result showed that the drying treatment could decreased the species and numbers of pathogenic bacteria in silkworm excrement obviously and improve the quality of medicinal materials. Compared with the lower ages, silkworm excrement of fifth instar seems like to be more suitable for use in medicine. Illumina MiSeq high-throughput sequencing system provides a more accurate and scientific data resource for the study of bacteria in silkworm excrement.

Study of the detection and significance of intracellular bacterial communities in patient with catheter-associated urinary tract infections / 中华泌尿外科杂志

Objective To detection the urine of bacteria hyphae and intracellular bacterial communities in patients with indwelling urinary catheter and discuss intracellular bacterial comnmunities in the pathogenesis of catheter-related urinary tract infection.Methods From May 2014 to February 2016,95 cases with D-J stent indwelling were enrolled in this study,including 38 male patients and 57 female patients.The mean age was (43 ±21)years old,ranging from 25 to 83 years old.We recorded those patient g clinical symptoms,middle urine culture results.If the middle urine culture was positive,further pathology test and scanning electron microscopy for bacteria hyphae and intracellular bacterial communities would be considered.Results The middle urine culture showed positive in 21 cases (22％,21/95);The classification of bacteria included E.coli in 11 cases,dung enterococcus in 2 cases,klebsiella pneumonia in 4 cases,pseudomonas aeruginosa in 3 cases,epidermis staphylococcus aureus in 1 case.Among those 21 patients,9 cases had the symptoms of fever and shiver.Urine pathology testing found hyphae in 6 cases (6％,6/95).all others were E.coli infection.For scanning electron microscope,6 cases were found rodshaped bacteria and hyphae.3 cases were found intracellular bacterial communities.Conclusions The presence of intracellular bacterial communities made urothelial itself the source of endogenous bacteria of urinary tract infection.Catheter-related urinary tract infections in patients with recurrence maybe basically homology bacteria.

Persistence of uropathogenic Escherichia Coli in the bladders of female patients with sterile urine after antibiotic therapies / 华中科技大学学报（医学）（英德文版）

This study aimed to provide evidence of persistent uropathogenic Escherichia coli (UPEC) in female patients with recurrent urinary tract infection (UTI) after antibiotic therapy. We collected biopsies of the bladder, and clean-catch urine samples from 32 women who had episodes of recurrent UTI and were given antibiotic therapy. Urine samples and biopsies were analyzed by conventional bacteriological techniques. Phylogenetic group and 16 virulence factors (VFs) of UPEC were determined using polymerase chain reaction (PCR). The infection capability of UPEC was confirmed in a mouse model. Immunofluorescence and electron microscopy were used to detect intracellular bacterial communities (IBCs) in the mouse model. The results showed that all urine specimens were detected sterile. E. coli was found in 6 of 32 biopsies (18.75%), and was identified to be UPEC by PCR. Different VFs associated with the formation of IBCs were identified in all six UPEC isolates. Each UPEC isolate was capable of forming IBCs within the bladder epithelial cells of mice. In conclusion, UPEC with distinctive pathological traits and the capability of IBC formation was first found in the bladders of women after antibiotic therapy, suggesting that the IBC pathogenic pathway may occur in humans and it plays an important role in UTI recurrence.

Bioavailability of pollutants in bacterial communities of Rodrigo de Freitas Lagoon, Rio de Janeiro, Brazil

Processes involving heavy metals and other contaminants continue to present unsolved environmental questions. To advance the understanding of geochemical processes that involve the bioavailability of contaminants, cores where collected in the Rodrigo de Freitas lagoon, and analyzed for bacterial activity and metal concentrations. Results would suggest an extremely reducing environment where organic substances seem to be the predominant agents responsible for this geochemical process. Analytical data showed sulphate reduction to be the main agent driving this process, since this kind of bacteria was found to be active in all of the samples analyzed. Esterase enzyme production did not signal the influence of heavy metals and hydrocarbon concentrations and heavy metals were found to be unavailable for biota. However, correlation between results for bacterial biomass and the potentially mobile percentage of the total Ni concentrations would suggest a negative impact.

An Improved Protocol for Extraction of Metagenomic DNA from High Humus, Alkaline and Saline Soil of Chinampa for T-RFLP Fingerprinting Analysis.

Aims: The principle aim of this study was to obtain high quality metagenomic DNA from the high humus-containing, alkaline soils of the chinampas, an artificial sustainable agroecosystem. Study Design: Different protocols reported previously were tested and were modified to extract the metagenomic DNA. Quality of the DNA samples was evaluated by amplification of 16S rRNA gene with PCR and T-RFLP (Terminal Restriction Fragment Length Polymorphism) analysis. Place and Duration of Study: This study was performed in Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional during 2011-2012. Methodology: Four soil samples were collected from two chinampas at the depth of 0-30 cm and 30-60cm. A protocol started with repeated prewashing before the direct cell lysis with lysozyme followed by SDS treatments, frozen and melting cycling was developed which combined the DNA isolation and purification procedures. The 16SrRNA genes were amplified from the extracted metagenomic DNAs and were used for T-RFLP fingerprinting analysis. Results: The 16SrRNA genes were amplified from all the DNA extracts corresponding to the four soil samples and were successfully used in the T-RFLP analysis, which generated 25 to 109T-RFs in the four soil samples digested separately with the restriction endonucleases HaeIII, HhaI and MspI. Conclusion: The protocol developed in the present study could generate high molecular weight and high quality metagenomic DNA from soils with high content of humic materials, for which the other reported protocols were not functioned. This soil harboured very diverse and unique bacterial communities belonging to at least nine phyla that might contribute to the high soil fertility.