• Journal of Life Science
• /
• 제10권1호
• /
• pp.64-65
• /
• 2000

Insoluble phosphate-solubilizing bacteria are routinely screened by a plate assay method using Pikovskaya agar and a modified Pikovskaya medium. A modified Pikovskaya medium to improve the clarity of the yellow-colored halo has not necessarity improved the plate assay. Colonies of phosphate-solubilizing bacteria tested could be redily selected after 48 h of incubation by green-colored colony formation on plate in which bromcresol green(BCG) was included. Among them, two bacterial strains did not produce distinct yellow halos after 48 h of incubation. We suggest that the green colony formation on plate medium containing BCG is advantageous ofr rapid isolating phosphate-solubilizing bacteria directly from soil.

• 분석과학
• /
• 제7권2호
• /
• pp.173-179
• /
• 1994

빠른 시간내에 적은 시료로(mg 단위) FIA와 Diode Array Spectrophotometry를 이용하여 해리상수를 구할 수 있는 방법을 개발하는 데 실험의 비중을 두었고, 그 대상으로 Bromo Cresol Green을 사용하였다. 소량의 산 염기를 가할 때 제일 sensitive한 발색반응을 보이는 지시약의 pK는 7.0임이 컴퓨터에 의해 계산되었다. Spectrophotometry를 이용한 Bromothylmol Blue와 Bromocresol Green은 Kielland 방법에 의한 Activity를 보정해 준 후 pKa가 각각 7.31과 4.82를 얻었다(Reported value by Bishop 7.30, 4.79). FIA에 의한 Bromocresol Green의 pKa값은 4.78을 얻어 다른 방법과 유사함을 알 수 있었다.

• BMB Reports
• /
• 제38권3호
• /
• pp.343-349
• /
• 2005

Gamma-glutamyltransferase (GGT, EC 2.3.2.2) which hydrolyzes glutathione (GSH), is required for the maintenance of normal intracellular GSH concentration. GGT is a membrane enzyme present in leukocytes and platelets. Its activity has also been observed in human neutrophils. In this study, GGT was purified from Triton X-100 solubilized neutrophils and its kinetic parameters were determined. For kinetic analyses of transpeptidation reaction, $\gamma$-glutamyl p-nitroanilide was used as the substrate and glycylglycine as the acceptor. Apparent $K_m$ values were determined as 1.8 mM for $\gamma$-glutamyl p-nitroanilide and 16.9 mM for glycylglycine. The optimum pH of GGT activity was 8.2 and the optimum temperature was $37^{\circ}C$. It had thermal stability with 58% relative activity at $56^{\circ}C$ for 30 min incubation. L-serine, in the presence of borate, was detected as the competetive inhibitor. Bromcresol green inhibited neutrophil GGT activity as a noncompetetive inhibitor. The neutrophils seem to contain only the isoenzyme that is present in platelets. We characterized the kinetic properties and compared the type of the isoenzyme of neutrophil GGT with platelet GGT via polyacrylamide gel electrophoresis (PAGE) under a standart set of conditions.

• 생물정신의학
• /
• 제2권1호
• /
• pp.70-76
• /
• 1995

A few researchers have reported that major depression may be associated with higher levels of positive acute phase proteins(APPs), such as haptoglobin(Hp), ${\alpha}1$-antitrypsin(${\alpha}1AT$), ceruloplasmin(Cp) and lower levels of negative APPs(visceral proteins), such as albumin(Alb) and transferrin(Tf). Elevated levels of positive APPs and a drop in negative APPs constitute important indicators of immune activation. This study was designed to investigate whether altered serum concentrations of positive APPs and of negative APPs reflect the state of depression. Twenty patients who fulfilled DSM-III-R criteria for major depressive disorder and for dysthymic disorder and twelve normal healthy controls were included. The authors measured positive APPs(Hp, ${\alpha}1AT$, Cp) and negative APPs(Alb, Tf) using rate nephelometry and bromcresol green method. 1) There were significant increases of ${\alpha}1AT$, Cp in major depressed patients as compared with normal controls. Trends towards higher Hp and lower Alb, Tf in major depressed patients were observed. 2) No significant difference of APPs concentrations between dysthymic patients and normal controls was found. 3) Severity of depression(HDRS, BDI score) was related to Hp, Cp, ${\alpha}1AT$ value positively. Our findings are partially compatible with the hypothesis that major depression may be accompanied by acute phase response with higher levels of positive APPs and lower levels of negative APPs.