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This article describes simplified methodologies for the preparation and processing of acidophilic hyperthermophilic cultures. Research discusses the development of a low-cost bioreactor, a modified culture medium, and a high-throughput purification step utilizing a cation-exchange resin to cultivate and purify Sulfolobus solfataricus-secreted alpha-amylase.

The role of glycosyl hydrolase on the growth of Pyrococcus furiosus on carbohydrate-based media has been studied. P. furiosus is a hyperthermophilic archaeon that grows optimally at 100 degrees C and can thrive on peptide-based media in the presence of alpha-linked polysaccharides. Results indicated significant bacterial growth at 98 degrees C in the presence of beta-1,3- and beta-1,3-beta-1,4-glucans. Oligosaccharides were found to be the nutrients most effective in stimulating the growth of P. furiosus.

Protocols for the cultivation of Chlorobium tepidum in a 22-liter photobioreactor under optimal conditions have been developed. The protocols enumerate the conditions required for the green sulfur bacterium to thrive with sulfide as the sole electron source. The bacterium is notorious for its inability to grow on sulfide alone. C. tepidum could be grown at rates and final cell yields comparable to that with thiosulfate if the sulfide concentration is maintained below 0.1 mM and the culture redox potential is at -300 at plus or minus 20 mV.

A new rod-shaped hyperthermophilic archaeum, isolated from hot marine water, was found to grow best at 100 degrees centigrade and pH 7.0 by aerobic respiration and dissimilatory nitrate reduction. Its final product was revealed to be dinitrogen. The organism used organic and inorganic substances as substrates in the course of aerobic and anaerobic respirations. Elemental sulfur was found to hinder growth. The novel isolate was seen to be closely related to the genus Pyrobaculum and has been named Pyrobaculum aerophilum.

The fatty acid profile of 10 Thermus strains were examined for responses to changes in temperature. Results showed that levels of isobranched acids were higher at the higher temperature, while the unsaturated fatty acids were higher at the lower temperature. Based on the relative proportion of fatty acids, three chemotaxonomic groups were formed. Membrane fluidity was also related to fatty acid composition and ratios. The ratio of iso C(sub15:0) to iso C(sub 17:0) was the most significant composition determinant, as well as the relative contributions of anteiso C(sub 15:0), anteiso C(sub 17:0) and anteiso C(sub 17:1).

The isolation of thermotolerant Gluconobacter strains that provide a new promising option for industrial production of 5-keto-D-gluconic acid (5KGA) at 37 degree Celsius is reported. The results suggested that the activity of pyrroloquinoline quinone (PQQ)-dependent glycerol dehydrogenase which contributes to 5KGA production increased in response to addition of PQQ and Ca[Cl.sub.2] in vitro when cells were grown at 37 degree Celsius.

A study was conducted to examine the effects of silicic acid on the growth of Thermus thermophilus TMY, an extreme thermophile isolated from a siliceous deposit formed from geothermal water at a geothermal power plant in Japan. A silica-induced protein (Sip) isolated from the cell envelope fraction of log-phase TMY cells grown in the presence of supersaturated silicic acid offer new insight into the growth and biosilisification associated with thermophiles in geothermal environments.

Isolating and purifying the active principle from the culture supernatant was used to decide chemical structure of putative self-growth inhibitor produced by symbiobacterium thermophilum. Results conclude that Bacillus proves beneficiary for symbiobacterium thermophilum because it detoxify BII and BIE in the coculture.

The authors discuss their research on Thermotoga maritima cell-free extracts. The high-affinity glucose- and maltose-binding activities in these extracts have been detected, and the results demonstrate that in the presence of cognate sugar the expression of these binding-protein activities is repressed by T. maritima growth.

Research has been conducted on WD-repeat proteins discovered in eukaryotes. The authors describe the expression of WD-repeat protein PkwA in thermophilic actinomycete Thermomonospora curvata CCM3352, and demonstrate that this expression is limited to spore-derived growth exponential phase and that the protein's WD domain can undergo phophorylation in the presence of T. curvata membrane fractions.