• Korean journal of applied entomology
• /
• v.14 no.4 s.25
• /
• pp.209-213
• /
• 1975

This paper is a report of studies to determine the amino acid composition of Plant Pathogenic Corynebacteria and to assess whether these characteristics can be correlated with the taxonomic position of these organisms. The results indicated that plant pathogenic Corynebacteria contained on average less cystein, trypthophane, histidine, phenylalanine, isoleucin and total protein than did the other genera of bacteria. However, in general, the quantities of both cell protein and amino acids contained in bacterial cells were characteristics of the species or an individual strain of the organism and were not related to its classification.

• Proceedings of the Microbiological Society of Korea Conference
• /
• 2006.05a
• /
• pp.86-88
• /
• 2006

• Proceedings of the Microbiological Society of Korea Conference
• /
• 1999.04a
• /
• pp.57.1-57.1
• /
• 1999

• Korean Journal of Microbiology
• /
• v.22 no.4
• /
• pp.249-255
• /
• 1984

To develop the host-vector system for industrial Coryneform bacteria that seemed to be the most suitable microorganisms for molecular breeding of genes involved in the production of amion acids, nucleotides, and other products of industrial interest, broad host range E. coli plasmid R 1162 DNA was transformed into Brevibacterium ammoniagenes and the plasmids pKU6 isolated from a transformant was physically characterized. All other plasmids from the transformed cells except pKU6 exsisted as multimeric forms in Brevibacterium ammoniagenes. The plasmid DNA was retransformed into Corynebacterium glutamicum with a high frequency ($1.32{\times}10^{-1}$ per cell) and maintained stably both in Brevibacterium ammoniagenes and Corynebacterium glutamicum after 100 generations of cultures with 25-30 copy number per cell. The size of both plasmid pKU6 and plasmid R1162 were the same and restriction maps by EcoR I, Ava I, Pst I, Pvu II and Hinc II were also similar.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.4
• /
• pp.639-647
• /
• 2008

The heat-inducible expression vectors for Corynebacterium glutamicum and C. ammoniagenes were constructed by using the ${\lambda}O_L1$ and the cryptic promoters, CJ1 and CJ4 that express genes constitutively in C. ammoniagenes. Although the promoters were isolated from C. ammoniagenes, CJ1 and CJ4 were also active in C. glutamicum. To construct vectors, the $O_L1$ from the ${\lambda}P_L$ promoter was isolated and fused to the CJ1 and CJ4 promoters by recombinant PCR. The resulting artificial promoters, CJ1O and CJ4O, which have one ${\lambda}O_L1$, and CJ1OX2, which has two successive ${\lambda}O_L1$, were fused to the green fluorescent protein (GFP) gene followed by subcloning into pCES208. The expression of GFP in the corynebacteria harboring the vectors was regulated successfully by the temperature-sensitive cI857 repressor. Among them, C. ammoniagenes harboring plasmid pCJ1OX2G containing GFP fused to CJ1OX2 showed more GFP than the other ones and the expression was tightly regulated by the repressor. To construct the generally applicable expression vector using the plasmid pCJ1OX2G, the His-tag, enterokinase (EK) moiety, and the MCS were inserted in front of the GFP gene. Using the vector, the expression of pyrR from C. glutamicum was tried by temperature shift-up. The results indicated that the constructed vectors (pCeHEMG) can be successfully used in the expression and regulation of foreign genes in corynebacteria.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.10 no.3
• /
• pp.225-229
• /
• 2005

To investigate impediments to plasmid transformation in Brevibacterium flavum BF4 and B. lactofermentum BL1, cell surface barriers were determined by measuring growth inhibition whilst enzymatic barriers were determined by comparing DNA methylation properties. B. lactofermentum was more sensitive to growth inhibition by glycine than B. flavum. Release of cellular proteins during sonication was more rapid for B. lactofermentum than for B. flavum. Plasmid DNA (pCSL 17) isolated from B. flavum transformed recipient $McrBC^+$ strains of Escherichia coli with lower efficiency than $McrBC^-$. McrBC digestion of this DNA confirmed that B. flavum contain methylated cytidines in the target sequence of McrBc sequences but B. lactofermentum contained a different methylation pattern. DNA derived from the B. lactofermentum transformed recipient $EcoKR^+$ strains of E. coli with lower efficiency than $EcoKR^-$, indicating the presence of methylated adenosines in the target sequence of EcoK sequences. The present data describe the differences in the physical and enzymatic barriers between two species of corynebacteria and also provide some insight into the successful foreign gene expression in corynebacteria.

• Korean journal of applied entomology
• /
• v.14 no.3 s.24
• /
• pp.155-161
• /
• 1975

The results of studies on the synthesis of B group vitamins by plant pathogenic bacteria indicate that most bacteria utilize thiamine, nicotinic acid, biotin and P-Aminobenzoic acid as growth factors. Riboflavin (vitamin $B_2$) was produced by most bacterial genera including the Corynebacteria but with the exception of C. rathay and C.fasciant. The results suggest that the ability to produce riboflavin is not a generic characteristic of Corynebacterium, and that the accuracy of the ultra-violet light method (one of the diagnostic tests for potato bacterial ring rot disease caused by Corynebacterium sepedonicum) must he reconsidered.

• Microbiology and Biotechnology Letters
• /
• v.26 no.5
• /
• pp.387-392
• /
• 1998

Brevibacterium lactofermentum, a gram-positive bacteria, has both the diaminopimelate (DAP) pathway and meso-DAP-dehydrogenase (DDH) pathway for L-lysine biosynthesis. To investigate importance of DDH pathway and the related ddh gene in lysine production, we introduced site-specific mutagenesis technique. A 300 bp DNA fragment central to the meso-DAP-dehydrogenase gene (ddh) of B. lactofermentum was used to inactive chromosomal ddh gene via homologous recombination. Southern hybridization analysis confirmed that the chromosomal ddh gene was disrupted by the vector sequence. The B. lactofementum ddh mutant obtained have an inactive DDH pathway. The results reveal that inactivation of the ddh gene in B. lactofermentum leads to dramatic reduction of lysine production as well as decrease of the growth rate, indicating that the DDH pathway is essential for high-level lysine production as well as biosynthesis of meso-DAP.

• Korean Journal of Veterinary Research
• /
• v.15 no.2
• /
• pp.315-320
• /
• 1975

A total of 364 quarter milk samples of 91 dairy cattle from 4 area around Jeonju in Jeonbug area were examined for infection rate and causative abets of mastitis by the Laboratory Procedures used in the Connecticut Mastitis-Control Program. The results obtained were as follows: 1. One hundred and thirty quarters (35.7%) from 67 cows (73.6%) were found to be infected with mastitis. It was found that 5 (1.37%) of the infected quarters were clinical mastitis and all of the rest were subclinical mastitis (125 quarters). 2. The main causative agents were found to be Staphylococcus aureus (46 quarters), Streptococcus agalactiae (49 quarters), streptococcus disgalactiae (18 quarters), Steptococcus uberis (13 quarters). Corynebacteria, Coliform organisms, Pseudomonas were also occasionally found to be causative organisms. 3. Having examined the number of infection Quarter per head of mastitis dairy cattle samplings, major findings were that the average number of infection quarter to total dairy cattle examined was 1.4 quarters, and that average number of infection quarter to the infected cattle was 1.9 quarters.

• Korean Journal of Veterinary Research
• /
• v.10 no.1
• /
• pp.39-45
• /
• 1970

A total of 835 quarter milk samples of 212 dairy cows from 14 herds were examined for mastitis and the results obtained were as follows; 1. Three hundred and fifty-eight quarters(42.9%) from 149 cows(70.3%) were found to be infected with mastitis. It was found that 11(1.3%) of the infected quarters were clinical mastitis and all of the rest were subclinical mastitis. 2. Streptococcus agalactiae(62 quarters) and Staphylococcus aureus(42 quarters) were the main two causative organisms of the mastitis. Streptococcus dysgalactiae, Streptococcus uberis, other streptococci, Corynebacteria, and Yeast were also found to cause the infection. 3. The majority of Staphylococcus aureus strains were sensitive to penicillin, orbenin, terramycin, and leucomycin, however, the most of Streptococcus strains were sensitive to penicillin and orbenin only. 4. Penicillin and orbenin were highly effective in the treatment of mastitis, especially orbenin for Staph ylococcus aureus infection and penicillin for Streptococcal infection. 5. A mastitis control program for dairy farms in Korea was discussed and recommended.