Purification and Properties of a Thermostable Esterase ofBacillus stearothermophilusProduced by RecombinantBacillus brevis

ABacillus stearothermophilusEsterase Produced by a RecombinantBacillus brevisStabilized by Sulfhydryl Compounds

“…The purification fold was greater than the one (175-fold) in our previous report. 4 ) When assayed under standard conditions after incubation for 10 min in buffers of various pH at 65°C, the esterase was found to be most stable over a pH range of 7.5 to 8.5 and active at a broad pH range of 6.5 to 8.5 and showed a maximum activity at pH 7.5 (data not shown).…”

“…In our previous paper, we reported a purification of the enzyme and found that although the enzyme is thermostable, its stability was limited to 60°C only. 4) Further research was therefore directed towards increasing the thermo stability of the enzyme by modification of the excretion vector and making use of compounds to stabilize the enzyme. In the new plasmid constructed (PHSC60), the original promoter and putative signal sequence of the esterase gene have been replaced with those of the MWP promoter and signal sequence from B. brevis 47 (H. Takagi, unpublished result).…”

Heterologous expression of thermostable esterase gene from Geobacillus thermoleovorans YN under different expression promoters

“…Several intra-and extracellular carboxylesterases have been cloned, fully expressed or even partially characterized from various thermophiles (Amaki et al 1992;Kim et al 1997;Morana et al 2002;Gao et al 2003;Ewis et al 2004). This paper describes the expression of carboxylesterase from G. thermoleovorans YN under different expression promoters (pET-T7, pBlue-T7 and T7& kpL).…”

Purification, amino acid sequencing and thermostability of an extracellular low molecular weight esterase produced by Bacillus subtilis NRRL 41270 in fermentation

“…Several thermostable esterases have been reported from Bacillus species, including B. stearophilus, B. subtilis, B. licheniformis S-86 and Bacillus sp. RN2 and B. cereus [6][7][8][9][10].…”