ABSTRACT
To improve kitasamycin biosynthesis by Streptomyces kitasatoensis Z-7, the addition of two precursors, sodium acetate and ethyl acetate, to the fermentation medium was evaluated. Ethyl acetate was the most effective precursor compared with control conditions; In a 15-L fermentor, the kitasamycin titer was 21% higher when 0.48% ethyl acetate was added compared to control conditions. Content of the A5 component increased by 5.1%, and the A4 content decreased slightly compared to that of the control. During kitasamycin synthesis, intracellular and extracellular concentrations of acetic acid were higher for S. kitasatoensis Z-7 supplemented with ethyl acetate than for the non-supplemented strain, and the activities of acyl-CoA synthetases, acyl-phosphotransferases, and acyl-kinases were also significantly increased, suggesting that increased acetyl-CoA levels can explain the high kitasamycin titer. These findings may improve the industrial-scale production of kitasamycin for clinical use, and the addition of 0.48% ethyl acetate as precursors in the medium at the beginning of cultivation was a new method to mitigate the negative influence on the cell growth of excess precursor.
Para melhorar a biossíntese de kitasamicina por Streptomyces kitasatoensis Z-7, a adição de dois precursores, acetato de sódio e acetato de etila, ao meio de fermentação foi avaliada. O acetato de etila foi o precursor mais efetivo em comparação com as condições de controle; Em um fermentador de 15 L, o título de kitasamicina foi 21% maior quando 0,48% de acetato de etila foi adicionado em comparação com as condições de controle. O conteúdo do componente A5 aumentou 5,1%, e o conteúdo A4 diminuiu ligeiramente em comparação com o do controle. Durante a síntese de kitasamicina, as concentrações intracelulares e extracelulares de ácido acético foram maiores para S. kitasatoensis Z-7 suplementado com acetato de etila do que para a cepa não suplementada, e as atividades de acil-CoA sintetases, acil-fosfotransferases e acil-cinases também foram significativamente aumentadas, sugerindo que níveis aumentados de acetil-CoA podem explicar o alto título de kitasamicina. Esses achados podem melhorar a produção em escala industrial da kitasamicina para uso clínico, e a adição de 0,48% de acetato de etila como precursores no meio no início do cultivo foi um novo método para mitigar a influência negativa no crescimento celular do excesso de precursor.
Subject(s)
Streptomyces , Kitasamycin , Fermentation , Anti-Bacterial AgentsABSTRACT
<p><b>AIM</b>To identify the components of acetylleucomycin and its hydrolytic products by LC-MS.</p><p><b>METHODS</b>Acetylleucomycin was separated on a Diamonsil C18 column with 0.1 mol x L(-1) ammonium acetate-acetontrile (35 : 65) as mobile phase. The LC-MS was equipped with an electorspray ion source (ESI), which was set at the positive ion mode, and the mass spectra of each component in chromatogram were obtained with difference cone voltage.</p><p><b>RESULTS</b>The components of acetylleucomycin and its hydrolytic products can be separated by HPLC. The components were identified according to the molecular weight and its major mass fragment ions. The major components identified in domastic acetylleucomycin were acetylleucomycin A4, A5; acetylleucomycin A1, A3; acetylleucomycin A6, A7, and acetylleucomycin A13. The hydrolytic products of acetylleucomycin were not kitasamycin, but some non-complete hydrolytic product.</p><p><b>CONCLUSION</b>The method is rapid, sensitive and specific. It' s suitable to application in the fields of multi-components antibiotics analysis.</p>
Subject(s)
Chromatography, Liquid , Methods , Hydrolysis , Josamycin , Chemistry , Kitasamycin , Chemistry , Leucomycins , Chemistry , Macrolides , Chemistry , Spectrometry, Mass, Electrospray Ionization , MethodsABSTRACT
This paper is presented to report the results of urinary quantitative culture and sensitivity tests of certain antibiotics. Studies were done on 331 cases from the Department of Urology. Woo Sok University Medical College Hospital during the period from May 1962 up to September 1970. 1) Urine specimens from 331 cases were cultured and, of these, 115 cases grew micro-organism while the remaining 216 cases showed no growth. Among the 115 cases, 84 cases(73%) revealed significant bacteriuria with counts over 10s/ml. colonies in urine while 31 cases(27%) were below 10(5)/ml. 2) Only 74 cases(88. 1%) among the 84 cases with significant bacteriuria could the bacteria be identified after centrifuging the specimens and doing a smear and Gram stain. 68 cases(81%) of the total 84 significant bacteriuria cases had shown urinary leukocyte count of more than 4/HPF while 16 cases(19%) were below 4/HPF. 3) 77 cases(92%) of the total 84 cases with significant bacteriuria had Gram negative bacilli while 4 cases had Gram positive cocci by direct smear. 4) There were no significant differences between male and female patients in colony counts except the female group revealed some preponderance of E. coli. 5) In the sensitivity testing if the cultured significant bacteriuria in the group with Gram negative bacilli, 36 cases(49.3%) were sensitive to Kanamycin and 22 cases(30.1%) were resistant, while all cases were resistant to leucomycin and only one case was sensitive to penicillin among the total 73 cases of Gram negative bacilli cultured.