The First Case of Otitis in Korea Caused by Brevibacterium otitidis

Brevibacterium spp. are gram-positive rods that are considered to be strictly nonpathogenic, and a very few cases of their infection in humans have been reported. In this study, we report a case of otitis caused by Brevibacterium otitidis. A 53-year-old woman, who visited the hospital, complained of symptoms, such as otorrhea from both ears, ear fullness, tinnitus, and hearing impairment, for several months. Ear discharge was cultured on blood agar for pathogen identification. Bacteria from the isolated colony were initially identified as Actinomyces odontolyticus by VITEK 2 (bioMerieux, France), whereas VITEK® MS (bioMerieux, France) identified them as Brevibacterium luteolum. Subsequently, bacteria from the isolated colony were confirmed as B. otitidis by 16S rRNA sequencing. Antimicrobial susceptibility testing confirmed their sensitivity to vancomycin and linezolid and resistance to clindamycin and penicillin. To our knowledge, this is the first reported case of otitis caused by B. otitidis in Korea.

Halotolerant bacteria in the São Paulo Zoo composting process and their hydrolases and bioproducts

Halophilic microorganisms are able to grow in the presence of salt and are also excellent source of enzymes and biotechnological products, such as exopolysaccharides (EPSs) and polyhydroxyalkanoates (PHAs). Salt-tolerant bacteria were screened in the Organic Composting Production Unit (OCPU) of São Paulo Zoological Park Foundation, which processes 4 ton/day of organic residues including plant matter from the Atlantic Rain Forest, animal manure and carcasses and mud from water treatment. Among the screened microorganisms, eight halotolerant bacteria grew at NaCl concentrations up to 4 M. These cultures were classified based on phylogenetic characteristics and comparative partial 16S rRNA gene sequence analysis as belonging to the genera Staphylococcus, Bacillus and Brevibacterium. The results of this study describe the ability of these halotolerant bacteria to produce some classes of hydrolases, namely, lipases, proteases, amylases and cellulases, and biopolymers. The strain characterized as of Brevibacterium avium presented cellulase and amylase activities up to 4 M NaCl and also produced EPSs and PHAs. These results indicate the biotechnological potential of certain microorganisms recovered from the composting process, including halotolerant species, which have the ability to produce enzymes and biopolymers, offering new perspectives for environmental and industrial applications.

The first reported catheter-related Brevibacterium casei bloodstream infection in a child with acute leukemia and review of the literature

Brevibacterium spp. are catalase-positive, non-spore-forming, non motile, aerobic Gram- positive rods that were considered apathogenic until a few reports of infections in immunocompromised patients had been published. To the best of our knowledge, this is the first report of B. casei catheter-related bloodstream infection in a child with acute leukemia. We aim to enhance the awareness of pediatric hematology and infectious disease specialists about this pathogen and review of the literature.

Misidentification of Brevibacterium casei as Propionibacterium acnes Isolated from the Blood of a Patient with Malignant Lymphoma / 대한임상미생물학회지

Brevibacterium spp. are Gram-positive, irregularly rod-shaped, strictly aerobic bacteria that resemble corynebacteria. Since they are a part of normal skin flora, they have been regarded as apathogenic, and human infections related to them are very rare. A 46-year-old man previously diagnosed with diffuse large B-cell lymphoma presented with fever without a definitive infectious source. Blood cultures from both peripheral blood and a central venous catheter showed that only aerobic bottles grew contaminants, while anaerobic bottles did not. Although the automated microbial identification system indicated Propionibacterium acnes, the isolated species was identified as B. casei by 16S rRNA sequence analysis. Our case emphasizes the utilization of 16S rRNA sequence analysis when the result from an automated system does not correspond with other laboratory findings. This is the first case of catheter-related blood stream infection due to B. casei identified by 16S rRNA sequence analysis.

Antimycobacterial activity of a Brevibacillus Laterosporus strain isolated from a moroccan soil

The treatment of tuberculosis has become more difficult with the worldwide spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis. Moreover, the prevalence of human disease caused by atypical mycobacteria has also increased in the past two decades and has further complicated the problem of the treatment of mycobacterial infections. It is therefore urgent to develop new highly active molecules against these bacteria. The present study reports the isolation from a Moroccan soil of a Bacillus strain that exhibits an important antimycobacterial activity. The strain was identified as Brevibacillus laterosporus using DNA sequencing of the 16S ribosomal RNA gene. The antimycobacterial activity was assigned to a substance with a protein nature. This nature was revealed using a liquid-liquid extraction with organic solvents, precipitation with ammonium sulfate and treatment with a protease. This study suggested the identification and the characterization of this active metabolite enabling therapeutic investigations further.

Medium optimization of protease production by Brevibacterium linens DSM 20158, using statistical approach

Various cultivation parameters were optimized for the production of extra cellular protease by Brevibacterium linens DSM 20158 grown in solid state fermentation conditions using statistical approach. The cultivation variables were screened by the Plackett-Burman design and four significant variables (soybean meal, wheat bran, (NH4)2SO4 and inoculum size were further optimized via central composite design (CCD) using a response surface methodological approach. Using the optimal factors (soybean meal 12.0g, wheat bran 8.50g, (NH4)2SO4) 0.45g and inoculum size 3.50%), the rate of protease production was found to be twofold higher in the optimized medium as compared to the unoptimized reference medium.

Consecutive episodes of peritonitis in a patient undergoing peritoneal dialysis caused by unusual organisms: Brevibacterium and Pantoea agglomerans

A 52-year-old man undergoing continuous ambulatory peritoneal dialysis presented with two consecutive episodes of peritonitis caused by unusual organisms, namely, Brevibacterium and Pantoea agglomerans. The patient was successfully treated with a 2-week course of cefazolin and ceftazidime for the Brevibacterium-associated peritonitis, and a 3-week course of gentamicin for the P. agglomerans-associated peritonitis. Although these environmental organisms are rarely responsible for human infection, the number of reported cases of human infection by these unusual organisms has increased. This report emphasizes the potential for infection by environmental organisms in patients undergoing peritoneal dialysis.

Overexpression of Corynebacterium glutamicum NAD kinase improves L-isoleucine biosynthesis / 生物工程学报

NAD kinase catalyzes the phosphorylation of coenzyme I [NAD(H)] to form coenzyme II [NADP(H)], and NADPH is an important cofactor in L-isoleucine biosynthesis. In order to improve NADPH supply, ppnK, the gene encoding NAD kinase in Corynebacterium glutamicum was cloned and separately expressed in an L-isoleucine synthetic strain, Brevibacterium lactofermentum JHI3-156, by an inducible expression vector pDXW-8 and a constitutive expression vector pDXW-9. Compared with the control strain JHI3-156/pDXW-8, NAD kinase activity of the inducible ppnK-expressing strain JHI3-156/pDXW-8-ppnK was increased by 83.5%. NADP(H)/NAD(H) ratio was also increased by 63.8%. L-isoleucine biosynthesis was improved by 82.9%. Compared with the control strain JHI3-156/pDXW-9, NAD kinase activity of the constitutive ppnK-expressing strain JHI3-156/pDXW-9-ppnK was increased by 220%. NADP(H)/ NAD(H) ratio and NADPH concentration were increased by 134% and 21.7%, respectively. L-isoleucine biosynthesis was increased by 41.7%. These results demonstrate that NAD kinase can improve the coenzyme II supply and L-isoleucine biosynthesis, which would also be useful for biosynthesis of other amino acids.

Central Venous Catheter-Related Microbacterium Bacteremia Identified by 16S ribosomal RNA Gene Sequencing / 대한임상미생물학회지

We describe here a case of central venous catheter (CVC)-related bacteremia caused by Microbacterium species in a 14-year-old patient, who had received chemotherapy for acute lymphoblastic leukemia. All nine blood cultures obtained from admission day 2 to day 62 yielded the same yellow-pigmented coryneform rod. Both Vitek 2 (bioMerieux, USA) and MicroScan (Dade Behring, USA) identified the isolate as Micrococcus species, and the API Coryne (bioMerieux, France) identified the isolate as Rhodococcus or Brevibacterium species. However, the 16S rRNA gene sequence showed a 99% identity with Microbacterium species. The bacteremia was recurrent or persistent over 60 days despite alternate systemic antibiotic therapy, but blood culture became negative after an addition of teicoplanin lock therapy for eradicating CVC-related bacteremia. This represents the first report of CVC-related Microbacterium bacteremia cured by antibiotic lock therapy in Korea.

Study on the kinetics of immobilized cells of Brevibacterium ammoniagenes MA-2 and Brevibacterium flavum MA-3 / 生物工程学报

The kinetics of immobilized cells of Brevibacterium ammoniagenes MA-2 and Brevibacterium flavum MA-3 cells were studied. By means of both a theoretical analysis of diffusion in the gel particles and an experimental determination of apparent kinetic parameters, the intrinsic kinetic parameters of immobilized cells of B. ammoniagenes MA-2 and B. flavum MA-3 cells were obtained.

Some enzymatic properties of cholesterol oxidase produced by Brevibacterium sp

In this study we determined some properties of cholesterol oxidase from a "Brevibacterium" strain isolated from buffalo's milk and identified the cholesterol degradation products by bacterial cell. A small fraction of the enzyme synthesized by cells cultured in liquid medium for 7 days was released into the medium whereas a larger fraction remained boud to the cell membrane. The extraction of this fraction was efficiently accomplished in 1 mM phosphate buffer, pH 7.0, containing 0.7(per cent) Triton X-100. The enzyme stability under freezing and at 45ºC was imrproved by addition of 20(per cent) glycerol. The optimum tempereature and pH for the enzyme activity were 53ºC and 7.5, respectively. The only steroidal product from cholesterol oxidation by the microbial cell and by the crude extract of the membrane-bound enzyme was 4-colesten-3-one. Chromatographic analysis showed that minor no steroidal compounds as well as 4-colesten-3-one found in the enzyme in the buffer solution. Cholesterol oxidation by the membrane-bound enzyme was a first order reaction type

Fermentation and recovery of L-glutamic acid from cassava starch hydrolysate by ion-exchange resin column

Investigators were carried out with the aim of producing L-glutamic acid from Brevibacterium sp. by utilizing a locally available starchy substrate, cassava (Manihot esculenta Crantz). Initial studies were carried out in skate flasks, which showed that even though the yield was high with 85-90 DE (Dextrose Equivalent value), the maximum conversion yield (-34 per cent) was obtained by using only partially digested starch hydrolysate, i.e. 45-50 DE. Fermentations were carried out in batch mode in a 5 L fermenter, using suitably diluted cassava starch hydrolysate, using a 85-90 DE value hydrolysate. Media supplemented with nutrients resulted in an accumulation of 21 g/L glutamic acid with a fairly high (66,3 per cent) conversation yield of glucose to glutamic acid (based on glucose consumed and on 81,74 per cent theoretical conversion rate). The bioreactor conditions most conductive for maximum production were pH 7.5, temperature 30§C and an agitation of 180 rpm. When fermentation was conducted in fed-batch mode by keeping the residual reducing sugar concentration at 5(per cent) w/v, 25,0 g/L of glutamate was obtained after 40 h fermentation (16 per cent more the batch mode). Chromatographic separation by ion-exchange resin was used for the recovery and purification of glutamic acid. It was further crystallized and separated by making use of its low solubility at the isoelectric point (pH 3.2).