14. "Biomimetic-dye affinity adsorbents for enzyme purification: application to the one-step purification of Candida boidinii formate dehydrogenase. "
N.E. Lambrou, A.D. Karagouni and Y.D. Klonis.
Biotechnology and Bioengineering, vol. 48, pages 278-288, (1995).   View at publisher's site   Request copy
Abstract: Formate dehydrogenase (FDH, EC 1.2.1.2) was purified from Candida boidinii cells in a single step by biomimetic- dye affinity chromatography. For this purpose, seven biomimetic analogues of the monochlorotriazine dye, Cibacronm Blue 3GA (CB3GA), and parent dichlorotriazine dye, Vilmafixa Blue A-R (VBAR), bearing a carboxylated structure as their terminal biomimetic moiety, were immobilized on crosslinked agarose gel, Ultrogelm A6R. The corresponding new biomimetic-dye adsorbents, along with nonbiomimetic adsorbents bearing CB3GA and VBAR, were evaluated for their ability to purify FDH from extracts obtained after press-disintegration of C. boidinii cells. Optimal conditions for maximizing specific activity of FDH in starting extracts (1.8 U/mg) were realized when cell growth was performed on 4% methanol, and press disintegration proceeded in four consecutive passages before the homogenate was left to stand for 1 h (4°C). When compared to nonbiomimetic adsorbents, biomimetic adsorbents exhibited higher purifying ability. Furthermore, one immobilized biomimetic dye, bearing as its terminal biomimetic moiety mercaptopyruvic acid linked on the chlorotriazine ring (BM6), displayed the highest purifying ability. Adsorption equilibrium data which were obtained for the BM6 adsorbent in a batch system corresponded well to the Langmuir isotherm and, in addition, breakthrough curves were taken for protein and FDH adsorption in a fixed bed of BM6 adsorbent. The dissociation constant (K,) of the complex between immobilized BM6 and FDH was found to equal 0.05 pM. Adsorbent BM6 was employed in the purification of FDH from a 18-L culture of C. boidinii in a single step (60% overall yield of FDH). The purified FDH afforded a single-band on sodium dodecyl sulphate polyacrylamide gel electrophoresis, and a specific activity of 7.0 U/mg (30°C).

13. "The effect of soil moisture content on spore germination, mycelium development and survival of a seeded streptomycete in soil. "
A.D. Karagouni, A.P. Vionis, P.W. Baker and E.M.H. Wellington.
Microbial Releases, vol. 2, pages 47-51, (1993).   View at publisher's site   Request copy
Abstract: No abstract available.

12. "A continuous-culture approach to the analysis of inorganic carbon concentration by Synechococcus species. "
S. Bloye, A.D. Karagouni and N.G. Garr.
FEMS Microbiology Letters, vol. 99, pages 79-84, (1992).   View at publisher's site   Request copy
Abstract: Chemostat cultures of Synechococcus PCC7942 were established in steady state over ten generations with inorganic carbon-limiting biomass production. The bicarbonate-concentration process was not significantly induced; RuBisCo activity was increased six-fold with decreasing dissolved inorganic carbon concentration and the presence of the 42-kDa cytoplasmic membrane polypeptide was observed but not implicated in the process.

11. "Isolation and identification of restriction endonuclease MspCI. "
M. Rina, M. Tzanodaskalaki, A. Karagouni, M. Pagomenou, I. Tsigos and V. Bouriotis.
Nucleic Acid Research, vol. 20, pages 1806, (1992).   View at publisher's site   Request copy
Abstract: No abstract available.

10. "Isolation and identification of restriction endonuclease SseBI. "
M. Rina, M. Tzanodaskalaki, A. Karagouni, M. Pagomenou, I. Tsigos and V. Bouriotis.
Nucleic Acid Research, vol. 20, pages 1808, (1992).   View at publisher's site   Request copy
Abstract: No abstract available.

9. "Isolation and identification of restriction endonuclease SseAI. "
M. Rina, A. Karagouni, M. Pagomenou, I. Tsigos and V. Bouriotis.
Nucleic Acid Research, vol. 19, pages 6341, (1991).   View at publisher's site   Request copy
Abstract: No abstract available.

8. "Isolation and identification of restriction endonuclease SgrBI. "
M. Rina, A. Karagouni, M. Pagomenou and V. Bouriotis.
Nucleic Acid Research, vol. 19, pages 6342, (1991).   View at publisher's site   Request copy
Abstract: No abstract available.

7. "Isolation and identification of restriction endonuclease BseBI. "
M. Rina, I. Tsigos, A. Karagouni, M. Pagomenou and V. Bouriotis.
Nucleic Acid Research, vol. 19, pages 4776, (1991).   View at publisher's site   Request copy
Abstract: No abstract available.

6. "The presence and absence of inorganic carbon concentration systems ιn unicellular cyanobacteria. "
A. D. Karagouni , S.A. Bloye and N. G. Garr.
FEMS Microbiology Letters, vol. 68, pages 137–141, (1990).   View at publisher's site   Request copy
Abstract: The response of eight species of unicellular cyanobacteria to growth under high and low CO2 regimes was measured by RuBisCO activity and the extent of inorganic carbon concentration. No significant increase in RuBisCO activity in CO 2- limited batch cultures was observed. The main feature of the data presented is the absence of a bicarbonate concentrating process in the oceanic, phycoerythrin-containing species examined, this is discussed in light of bicarbonate supply in freshwater and ocean environments.

5. "Evidence that protein B of the thiosulfate-oxiding system of Thiobacillus versutus contains a binuclear manganese cluster. "
R. Cammacj, Karagouni , A. Chapman, W.P. Lu, A. Karagouni and D. P. Kelly.
FEBS Letters, vol. 253, pages 239–243, (1989).   View at publisher's site   Request copy
Abstract: Manganese was shown to be an essential trace metal for growth and thiosulphate oxidation by Thiobacillus versutus in chemostat culture. In the thiosulphate-oxidizing enzyme system of T. versutus, protein B was the only component found to contain manganese in significant amounts. When it was examined by electron spin resonance (ESR) spectroscopy, protein B gave a broad, complex spectrum, indicative of the presence of a dimeric manganese cluster, with manganese in the Mn(II) oxidation state.

4. "Carbon dioxide fixation by Thiobacillus versutus: apparent absence of a CO2-concentrating mechanism in organisms grown under carbon-limitation in the chemostat. "
A. D. Karagouni and D. P. Kelly.
FEMS Microbiology Letters, vol. 58, pages 179–182, (1989).   View at publisher's site   Request copy
Abstract: Thiobacillus versutus responds to both CO 2- 1imitation and increase in chemostat dilution rate under thiosulphate-limitation by increasing ribulose bisphosphate carboxylase specific activity. It has no high affinity CO2-concentrating mechanism like that shown in Synechococcus, and may depend on diffusional uptake of CO2/HCO3.

3. "Screening of carob bean yeasts. Chemical composition of Schizosaccharomyces versatilis grown on aqueous carob extract"
S. G. Marakis and A. D. Karagouni.
Biotechnology Letters, vol. 7, pages 831–836, (1985).   View at publisher's site   Request copy
Abstract: An improved extraction procedure for soluble sugars and tannins from carob bean is described. The yeast flora of the carob is rich, with Saccharozyces predominant; an isolate of Schizosaccharomyces versatilis cultured in the aqueous extract utilizes tannins as well as sugars to give a high biomass and protein yield of good quality.

2. "Enzymes of the Calvin cycle and intermediary metabolism in the cyanobacterium Anacystis nidulans grown in chemostat culture"
A. D. Karagouni and J. H. Slater.
Journal of General Microbiology, vol. 115, pages 369-376, (1992).   View at publisher's site   Request copy
Abstract: The cyanobacterium Anacystis nidulans grown in light-limited and CO2-limited chemostat cultures showed varying rates of CO2 fixation with peaks at dilution rates of 0.10 to 0.12 h-1. The specific activities of a number of enzymes of the reductive and oxidative pentose phosphate and glycolytic pathways and the tricarboxylic acid and glyoxylate cycles varied significantly as a function of the growth environment (substrate limitation) and organism growth rate. Ribulose-1,5-bisphosphate carboxylase varied 15-fold under CO2-limited conditions but did not change under light-limited conditions. With the exception of phosphoribulokinase, all enzymes which showed a change in specific activity increased with decreasing dilution rate. The specific activities of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, hexokinase, ribulose-1,5-bisphosphate carboxylase and malate dehydrogenase were significantly higher in organisms grown under CO2-limited conditions than under light-limited conditions. Fructose-1,6-bisphosphate aldolase and phosphoribulokinase specific activities were similar at all growth rates and under both limitations. Isocitrate lyase was the only enzyme examined which showed higher specific activities under light-limited conditions. Thus Anacystis nidulans can selectively express different enzymes, possibly by transcriptional control.

1. "Growth of the blue-green alga Anacystis nidulans during washout from light-and carbon-limited chemostats"
A. D. Karagouni and J. H. Slater.
FEMS Microbiology Letters, vol. 4, pages 295-299, (1978).   View at publisher's site   Request copy
Abstract: No abstract available