1.Research progress in spore-based in-situ restoration technology of concrete with microorganisms.
Jianmiao XU ; Kaxi XIE ; Feng CHENG ; Dongxu JIA ; Zhiqiang LIU ; Yuanshan YANG
Chinese Journal of Biotechnology 2021;37(7):2351-2365
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
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Calcium Carbonate
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Construction Materials
;
Spores, Bacterial
;
Technology
2.Sporulation or competence development? A genetic regulatory network model of cell-fate determination in Bacillus subtilis.
Zhenghui LU ; Yuling ZHOU ; Xiaozhou ZHANG ; Guimin ZHANG
Chinese Journal of Biotechnology 2015;31(11):1543-1552
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
3.Development and comparative evaluation of up-converting phosphor technology based lateral flow assay for rapid detection of Yersinia pestis, Bacillus anthracis spore and Brucella spp.
Chunfeng LI ; Pingping ZHANG ; Xiaoying WANG ; Xiao LIU ; Yong ZHAO ; Chongyun SUN ; Chengbin WANG ; Ruifu YANG ; Lei ZHOU
Chinese Journal of Preventive Medicine 2015;49(1):3-8
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
4.Efficacy of Diphenyleneiodonium Chloride (DPIC) Against Diverse Plant Pathogens
Boknam JUNG ; Taiying LI ; Sungyeon JI ; Jungkwan LEE
Mycobiology 2019;47(1):105-111
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
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Anti-Bacterial Agents
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Burkholderia
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Cell Proliferation
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Flowers
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Germination
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Head
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NADPH Oxidase
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Plants
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Spores, Fungal
;
Superoxides
5.Comparison of Perasafe(R) with Cidex(R) for Cidal Activities Against Bacteria, Yeast, Mycobacteria and Bacterial Spores.
Hyo Won LEE ; Mi Na KIM ; Yeon Jeong PYO ; Chik Hyun PAI
Korean Journal of Nosocomial Infection Control 2001;6(2):95-102
BACKGROUND: Glutaraldehyde is used most commonly as a high-level disinfectant for semicritical patient-care equipments. However, its potential toxicity to healthcare workers and a long exposure time needed to kill mycobacteria can be problematic. Recently, Perasafe(R) (Antec International, UK) has been introduced in the market as a safe and very effective disinfectant. This study was to evaluate the efficacy of Perasafe(R) against not only bacteria and yeast but also mycobacteria and bacterial spores and compare it with glutaraldehyde. MATERIAL AND METHOD: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Mycobacterium tuberculosis, and Bacillus subtilis were used for the test. Perasafe(R) and Cidex(R) were used at the final concentration of 1.62% and 2.25%, respectively; the disinfectants were neutralized by Tween 80 (0.5%) in the mycobacterial test and by lecithin (0.75%) in all other tests. Bacterial suspensions were made in phosphate buffer with or without fetal bovine serum (1%) to simulate dirty or clean conditions, respectively. The disinfectants were tested at 0, 24 and 48 hr of preparation to check stability. An effective disinfectant activity was defined as a 5 log10 reduction in viable counts. RESULTS: E. coli, S. aureus, P. aeruginosa and C albicans were effectively disinfected in less than 5 min by both Perasafe(R) and Cidex(R) and the both disinfectants remained equally effective under the dirty conditions or at 48 hr of preparation. Perasafe(R) was effective in 1 min against B. subtilis spores compared to Cidex(R) which took 30 min for the same activity. M. tuberculosis was effectively disinfected in 10 min by Perasafe(R) and 20 min by Cidex(R). CONCLUSIONS: Perasafe(R) showed greater tuberculocidal and sporicidal activities than Cidex(R), although both disinfectants were equally effective against common bacterial and yeast pathogens. Perasafe(R) may be an outstanding high-level disinfectant for endoscopes and other semicritical medical equipment.
Bacillus subtilis
;
Bacteria*
;
Candida albicans
;
Delivery of Health Care
;
Disinfectants
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Endoscopes
;
Escherichia coli
;
Glutaral
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Lecithins
;
Mycobacterium tuberculosis
;
Polysorbates
;
Pseudomonas aeruginosa
;
Spores
;
Spores, Bacterial*
;
Staphylococcus aureus
;
Suspensions
;
Tuberculosis
;
Yeasts*
6.Surface display of GFP using CotX as a molecular vector on Bacillus subtilis spores.
Qian LI ; Degang NING ; Chundu WU
Chinese Journal of Biotechnology 2010;26(2):264-269
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
7.A Case of Tinea Barbae.
Sun Wha LEE ; Byung In RO ; Chin Yo CHANG
Korean Journal of Dermatology 1982;20(5):795-799
Tinea barbae is one of the relatively rare chronic dermatophytosis of adult male, developing on the beard and moustache area of the face. We observed in a 50-year-old male patient who showed atypical clinical findings of tinea barbae. Initially, we impressed sycosis vulgaris, due to diffuse multiple pustular nodules with swelling on the beard area and both cheek of the face. We had treated him by antibiotics anri no improvement was noticed. On the 20th day from first visit, Trichophyton mentagrophytes was identified, and histopathologic exam revealed many spores and hyphae on the hair follicle. His skin lesions were almostly cleared after injestion of 5 months period of griseofulvin.
Adult
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Anti-Bacterial Agents
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Cheek
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Folliculitis
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Griseofulvin
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Hair Follicle
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Humans
;
Hyphae
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Male
;
Middle Aged
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Skin
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Spores
;
Tinea*
;
Trichophyton
8.A Case of Kerion Celsi Caused by Microsporum canis in Adult Man.
Seung Han LEE ; Woo Young SIM ; Mu Hyoung LEE ; Nack In KIM ; Choong Rim HAW ; Tae Yeon YOO
Korean Journal of Dermatology 1990;28(1):80-84
Kerion celsi is an inflammatory type of tinea capitis. We report a case of Kerion celsi caused by Micropsporum canis in 51 year-old man. When he visited our hospital, he suffered from hair loss and erythematous scaly patched and pustules on the scalp and papules on the face with tenderness and itching sensation. Cultures from scalp lesion and infected hair on Sabouraud glucose agar media showed Microsporum canis. Histopathologic findings showed graunlomatous changes in dermis and many spores around the hair shaft. Treatment was done topically with antifungal ointment and systernically with antibiotics, steroid and antifungsl agents. It is uncommon in adults, especially in men, but this condition must be considered when clinicians are evaluating patients with hair loss and nonspecific scalp dermatitis.
Adult*
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Agar
;
Anti-Bacterial Agents
;
Dermatitis
;
Dermis
;
Glucose
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Hair
;
Humans
;
Male
;
Microsporum*
;
Middle Aged
;
Pruritus
;
Scalp
;
Sensation
;
Spores
;
Tinea Capitis*
9.A Case of Pseudomembranous Colitis due to Clostridium difficile.
Jung Hyun LEE ; Young Yoo KIM ; Joon Sung LEE
Journal of the Korean Pediatric Society 1996;39(9):1320-1325
Pseudomembranous colitis may result from abnormal growth of toxigenic strains of Clostridium difficile associated with antibiotic-induced alteration of the colonic microbiologic flora. C. difficile, a spore forming gram positive obligate anaerobic bacillus, is part of the normal flora and known to be the major cause of pseudomembranous colitis. We experienced a case of pseudomembranous colitis in a 14-month-old male presented with bloody mucoid diarrhea and fever who had received broad spectrum antibiotics for the treatment of pneumonia. This case was diagnosed with sigmoidoscopy and confirmed by isolation of the organism on culture with selective media TCCFA. All antibiotics were discontinued and vancomycin was administrated orally. He showed a good response.
Anti-Bacterial Agents
;
Bacillus
;
Clostridium difficile*
;
Clostridium*
;
Colon
;
Diarrhea
;
Enterocolitis, Pseudomembranous*
;
Fever
;
Humans
;
Infant
;
Male
;
Pneumonia
;
Sigmoidoscopy
;
Spores
;
Vancomycin
10.A Case of Pseudomembranous Colitis due to Clostridium difficile.
Jung Hyun LEE ; Young Yoo KIM ; Joon Sung LEE
Journal of the Korean Pediatric Society 1996;39(9):1320-1325
Pseudomembranous colitis may result from abnormal growth of toxigenic strains of Clostridium difficile associated with antibiotic-induced alteration of the colonic microbiologic flora. C. difficile, a spore forming gram positive obligate anaerobic bacillus, is part of the normal flora and known to be the major cause of pseudomembranous colitis. We experienced a case of pseudomembranous colitis in a 14-month-old male presented with bloody mucoid diarrhea and fever who had received broad spectrum antibiotics for the treatment of pneumonia. This case was diagnosed with sigmoidoscopy and confirmed by isolation of the organism on culture with selective media TCCFA. All antibiotics were discontinued and vancomycin was administrated orally. He showed a good response.
Anti-Bacterial Agents
;
Bacillus
;
Clostridium difficile*
;
Clostridium*
;
Colon
;
Diarrhea
;
Enterocolitis, Pseudomembranous*
;
Fever
;
Humans
;
Infant
;
Male
;
Pneumonia
;
Sigmoidoscopy
;
Spores
;
Vancomycin