Concrete is the most widely used modern building material. It is easy to crack under the action of stress, which makes the concrete structure permeable, affecting the durability and integrity of the structure, and thus shortening its service life. Microbial in-situ remediation technology is a low cost, effective and green way for concrete crack repairing. Due to its excellent biocompatibility, service life elongation, economic losses and environmental pollution reduction, microbial in-situ remediation technology has been intensively investigated. Bacillus has attracted much attention because of its excellent biomineralization ability, extremely strong environmental tolerance and long-term survival ability of its spores. In order to promote the research, development and large-scale application of microbial in-situ healing of concrete, the paper reviews the mechanism of spore-based in-situ healing of concrete, the survival of spores exposed in concrete, the influence of spores and external additives on the mechanical properties of concrete, progress in research and development of healing agent as well as healing effects. Moreover, future research focuses such as improving the survival ability of spores in the harsh environment of concrete, reducing the influence of external additives on the mechanical properties of concrete, and strengthening the healing effect of actual field applications are also summarized.
Bacillus ; Calcium Carbonate ; Construction Materials ; Spores, Bacterial ; Technology

Many of the fungicides and antibiotics currently available against plant pathogens are of limited use due to the emergence of resistant strains. In this study, we examined the effects of diphenyleneiodonium chloride (DPIC), an inhibitor of the superoxide producing enzyme NADPH oxidase, against fungal and bacterial plant pathogens. We found that DPIC inhibits fungal spore germination and bacterial cell proliferation. In addition, we demonstrated the potent antibacterial activity of DPIC using rice heads infected with the bacterial pathogen Burkholderia glumae which causes bacterial panicle blight (BPB). We found that treatment with DPIC reduced BPB when applied during the initial flowering stage of the rice heads. These results suggest that DPIC could serve as a new and useful antimicrobial agent in agriculture.
Agriculture ; Anti-Bacterial Agents ; Burkholderia ; Cell Proliferation ; Flowers ; Germination ; Head ; NADPH Oxidase ; Plants ; Spores, Fungal ; Superoxides

A 46-year-old male presented with skin lesion on the tip of penis, occurring a month ago. Erythematous macules and grouped vesicles on the glans penis and upper side of prepuce area were noticed. In addition, scales were noticed on the tip of glans penis. The lesion was first diagnosed as herpes genitalis based on the clinical manifestation, but had failed to improve with systemic and topical antiviral and topical antibiotics. KOH examinations were performed on his upper glans penis, and we detected pseudo hyphae and spores. Fungal culture and polymerase chain reaction (PCR) study were revealed as Candida albicans. He was successfully treated with topical isoconazole cream twice a day. Candida balanitis refers to candida infections of glans penis. Infectious balanitis presented various clinical presentations, it is not easy to diagnose with clinical presentation only. Therefore, it is essential to include other examination such as KOH examination, microorganism exam, and/or biopsy in the differential diagnosis when cutaneous lesions are noticed in patients. Herein, we present a candida balanitis with atypical features that clinically mimicked herpes genitalis.
Anti-Bacterial Agents ; Balanitis* ; Biopsy ; Candida albicans ; Candida* ; Diagnosis, Differential ; Herpes Genitalis* ; Humans ; Hyphae ; Male ; Middle Aged ; Penis ; Polymerase Chain Reaction ; Skin ; Spores ; Weights and Measures

OBJECTIVETo develop an up-converting phosphor technology based lateral flow (UPT-LF) assay for rapid and quantitative detection of Yersinia pestis, Bacillus anthracis spore and Brucella spp.and make the comparison with BioThreat Alert (BTA) test strips (Tetracore Inc., USA).

METHODSUsing up-converting phosphor nano-particles (UCP-NPs) as the bio-marker, three double-antibody-sandwich model based UPT-LF strips including Plague-UPT-LF, Anthrax-UPT-LF, Brucella-UPT-LF were prepared and its sensitivity, accuracy, linearity and specificity were determined by detecting 10(10), 10(9), 10(8), 10(7), 10(6), 10(5) and 0 CFU/ml series of concentrations of Y.pestis, B.anthracis, Brucella standards and other 27 kinds of 10(9) CFU/ml series of contrations of bacteria strains.Furthermore, the speed, sensitivity and accuracy of bacteria standards and simulated sample detection were compared between UPT-LF and BTA system.

RESULTSThe detection limit of Plague-UPT-LF, Anthrax-UPT-LF and Brucella-LF was 10(5) CFU/ml. The CV of series of bacteria concentrations was ≤ 15%, and the r between lg (T/C-cut-off) and lg (concentration) was 0.996,0.998 and 0.999 (F values were 1 647.57, 743.51 and 1 822.17. All the P values were <0.001), respectively. The specificity of Plague-UPT-LF and Brucella-LF were excellent, while that of Anthrax-UPT-LF was a little bit regretful because of non-specific reaction with two isolates of B. subtilis and one B.cereus. On-site evaluation showed the detection time of UPT-LF for all Y.pestis, B.anthracis spore and Brucella spp.was 33, 36 and 37 min, while BTA was 115, 115 and 111 min, which revealed the higher detection speed and sensitivity of UPT-LF comparing with BTA. The negative rate of two methods for blank standard was both 5/5, the sensitivity of UPT-LF for Y.pestis,B.anthracis spore and Brucella spp. was all 10(5) CFU/ml, then BTA was 10(6), 10(6) and 10(5) CFU/ml, respectively. The detection rate of UPT-LF for all three bacteria analog positive samples was 16/16, while BTA for B.anthracis was 7/16 only.

CONCLUSIONThe good performance including rapidness, simplicity and high sensitivity will bring the bright future of UPT-LF to be broadly used on-site as first response to bio-terrorism.

Bacillus anthracis ; Brucella ; Immunochromatography ; Plague ; Sensitivity and Specificity ; Spores, Bacterial ; Yersinia pestis

Bacillus subtilis is a generally recognized as safe (GRAS) strain that has been widely used in industries including fodder, food, and biological control. In addition, B. subtilis expression system also plays a significant role in the production of industrial enzymes. However, its application is limited by its low sporulation frequency and transformation efficiency. Immense studies have been done on interpreting the molecular mechanisms of sporulation and competence development, whereas only few of them were focused on improving sporulation frequency and transformation efficiency of B. subtilis by genetic modification. The main challenge is that sporulation and competence development, as the two major developmental events in the stationary phase of B. subtilis, are regulated by the complicated intracellular genetic regulatory systems. In addition, mutual regulatory mechanisms also exist in these two developmental events. With the development of genetic and metabolic engineering, constructing genetic regulatory networks is currently one of the most attractive research fields, together with the genetic information of cell growth, metabolism, and development, to guide the industrial application. In this review, the mechanisms of sporulation and competence development of B. subtilis, their interactions, and the genetic regulation of cell growth were interpreted. In addition, the roles of these regulatory networks in guiding basic and applied research of B. subtilis and its related species were discussed.
Bacillus subtilis ; genetics ; physiology ; Gene Regulatory Networks ; Metabolic Engineering ; Spores, Bacterial ; physiology

Clostridium (C.) difficile is a common cause of nosocomial diarrhea in horses. Vancomycin and metronidazole have been used as standard treatments but are only moderately effective, which highlights the need for a novel alternative therapy. In the current study, we prepared antiserum of equine origin against both C. difficile toxins A and B as well as whole-cell bacteria. The toxin-neutralizing activities of the antibodies were evaluated in vitro and the prophylactic effects of in vivo passive immunotherapy were demonstrated using a conventional mouse model. The data demonstrated that immunized horses generated antibodies against both toxins A and B that possessed toxin-neutralizing activity. Additionally, mice treated with the antiserum lost less weight without any sign of illness and regained weight back to a normal range more rapidly compared to the control group when challenged orally with 10(7) C. difficile spores 1 day after serum injection. These results indicate that intravenous delivery of hyperimmune serum can protect animals from C. difficile challenge in a dose-dependent manner. Hence, immunotherapy may be a promising prophylactic strategy for preventing C. difficile infection in horses.
Animals ; Antibodies, Bacterial/blood/*immunology/therapeutic use ; Bacterial Proteins/immunology/therapeutic use ; Bacterial Toxins/immunology/therapeutic use ; Clostridium Infections/microbiology/prevention & control/*veterinary ; Clostridium difficile/*immunology ; Enterotoxins/immunology/therapeutic use ; Female ; Horse Diseases/microbiology/*prevention & control ; Horses ; Immune Sera/*immunology ; Immunization, Passive/*veterinary ; Mice ; Mice, Inbred C57BL ; Spores, Bacterial/immunology

We report a case of the isolation of the Aspergillus versicolor complex, initially misidentified by morphological characteristics as the Scopulariopsis species, from a homograft with a bicuspidalized pulmonary valve. An eighteen-month-old female, who had critical pulmonary stenosis, underwent pulmonary valve replacement. On postoperative day 8, she developed a fever, which did not respond to empiric broad-spectrum antibiotics. While no definitive source was identified, a filamentous fungus was isolated from the thawed homograft tissue culture prior to implantation on the operation day. The colonies were powdery green with white edges on Sabouraud dextrose agar. Microscopic examination showed septate hyphae with branched conidiophores and chains of spiny conidia, which suggested Scopulariopsis species. After direct sequencing of the internal transcribed spacer (ITS) regions, the fungus was identified as the A. versicolor complex. To our knowledge, the isolation of the A. versicolor complex from a homograft valve has not been previously described. This case shows that laboratory staff should be aware that microscopic morphology of the A. versicolor complex can resemble that of a number of other genera, including Scopulariopsis species.
Agar ; Anti-Bacterial Agents ; Aspergillus ; Bicuspid ; European Continental Ancestry Group ; Female ; Fever ; Fungi ; Glucose ; Humans ; Hyphae ; Pulmonary Valve ; Pulmonary Valve Stenosis ; Scopulariopsis ; Spores, Fungal ; Transplantation, Homologous

Spore coat proteins, such as CotB, CotC, CotG et al, are able to efficiently display exogenous protein on spore surface for preparing oral vaccines or enzymes. CotX is another structural protein of spore coats of Bacillus subtilis. To investigate whether CotX could carry target protein onto the spore surface, we constructed a recombinant integrative plasmid, designated as pJS749, which carries a recombinant cotX-gfp gene under the control of the cotX promoter. We transformed pJS749 into Bacillus subtilis 168(trp-), an alpha-amylase inactivated mutant DRJS749 was selected and confirmed to be a double crossover integrant, where cotX-gfp fragment was integrated into the chromosome. After induction of spore formation, significant green fluorescence was observed on spore surface of strain DRJS749 under fluorescent microcopy. This suggests that CotX is associated with the outer part of the coat. CotX can therefore be used as a molecular vehicle for spore surface display of exogenous proteins.
Bacillus subtilis ; genetics ; metabolism ; physiology ; Bacterial Proteins ; biosynthesis ; genetics ; Gene Expression Regulation, Bacterial ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Spores, Bacterial ; genetics ; metabolism

Spore surface display is one of attractive microorganism surface display systems. With the advantage of resistance attribute and specific assembly pattern, the technology of spore surface display now is attracting more and more attention. According to the current reports and main achievements of spore surface display, the structure and assembly of spores, the principle for construction and some existing spore surface display systems were elaborated in this paper. Now with the unique property of spores, the technique is not only widely used in production of vaccines but also has great applied potential in the field of biocatalysis and cell-factory.
Bacillus subtilis ; genetics ; metabolism ; Biocatalysis ; Biotechnology ; methods ; Gene Expression Regulation, Bacterial ; Genetic Engineering ; methods ; Recombinant Proteins ; genetics ; metabolism ; Spores, Bacterial ; genetics ; metabolism ; Tetanus Toxoid ; genetics ; immunology

OBJECTIVETo investigate the effect of low-temperature plasma on inactivation of bacterial spores and explore the mechanism.

METHODSDielectric barrier discharge (DBD) was employed to generate the atmospheric low-temperature plasma for treatment of B.subtilis var. niger spores with the gas spacing of 3, 4 and 5 and treatment time intervals of 5, 10, 15, 20, 25, 30 and 35 s. The survived colonies was counted with plate counting method, and the killing log value (KLV) at different treatment times was calculated. The inactivation effect of electric field on B.subtilis var.niger spores was also investigated and the spores treated with low-temperature plasma were observed with transmission electron microscope.

RESULTSWith the gap spacing of 3, 4 and 5 mm, the KLV of low-temperature plasma on B.subtilis var.niger spores within 25, 30 and 35 s of exposure was more than 5. The germicidal effects of the electric field on B. subtilis var.niger spores were rather poor. Transmission electron microscopy demonstrated total destruction of the surface and interior structure of the spores by low-temperature plasma.

CONCLUSIONSLow-temperature plasma is effective for inactivation of the bacterial spores with a time and dose dependence. The penetrating effect of charged particles and oxygenation effect of the reactive oxygen species might play a dominant role in plasma-induced bacterial spore inactivation, while the role of electric field is negligible.

Bacillus subtilis ; growth & development ; Cold Temperature ; Microbial Viability ; Plasma Gases ; pharmacology ; Spores, Bacterial ; growth & development ; Sterilization ; methods