Enhancement of Excretory Production of an Exoglucanase from Escherichia coli with Phage Shock Protein A (PspA) Overexpression

Subcellular localization, interactions and dynamics of the phage‐shock protein‐like Lia response in Bacillus subtilis

“…Mutants in psp genes often show only mild phenotypes but available data so far points to a function of PspABC in protecting and stabilizing the membrane against leakage and loss of membrane potential (Kobayashi et al ., ; Vrancken et al ., ; Horstman and Darwin, ). Moreover, the PSP response also seems to be important for virulence (Karlinsey et al ., ; Yamaguchi and Darwin, ) and protein secretion (Jones et al ., ; DeLisa et al ., ; Seo et al ., ; Wang et al ., ; Mehner et al ., ).…”

Synergistic hydrolysis of filter paper by recombinant cellulase cocktails leveraging a key cellobiase, Cba2, of Cellulomonas biazotea

“…In the past 2 decades, 5 genes encoding five individual cellobiases: Cba ( Wong et al, 1998 ; Chan, 2012 ; Chan et al, 2018 ), Cba2 ( Siddique et al, 2021 ; this study), Cba3 ( Chan et al, 2012 , Chan et al, 2018 ), Cba4 ( Chan et al, 2018 ), and Cba5 ( Chan et al, 2018 ) have been cloned and characterized by our group. Concurrently, we have also been actively involved in the engineering of various E. coli and B. subtilis expression systems applicable for the production of various recombinant proteins ( Lam et al, 1998 ; Sivakesava et al, 1999 ; Fu et al, 2006 ; Wang et al, 2011 ; Wong et al, 2012 ; Kwong et al, 2013 ; Kwong and Wong, 2013 ; Kwong et al, 2016a ; Kwong et al, 2016b ; Hu et al, 2018 ; Wong et al, 2019 ). Exploiting appropriately selected E. coli systems, Cba, Cba3, Cba4, and Cba5 as well as CenA and Cex were produced as recombinant proteins in adequate quantities for use in synergistic studies ( Table 3 ).…”

“…Through the studies, vast amounts of data have been gathered on the sequences of various cellulase genes, as well as the functional and structural properties of the encoded cellulase products. On the other hand, genetic engineering has enabled the development of innovative strategies and expression systems for the efficient production of heterologous cellulases ( Skipper et al, 1985 ; Wong et al, 1988 ; Lam et al, 1997 ; Lam et al, 1998 ; Fu et al, 2006 ; Wang et al, 2010 ; Wang et al, 2011 ; Wong et al, 2012 ; Kwong et al, 2016a ; Singh et al, 2017 ; Hu et al, 2018 ; Wong et al, 2019 ). The availability of recombinant approaches for cellulase expression does not only facilitate the engineering of feasible tactics and platforms for the large-scale production of cellulases ( Juturu and Wu, 2014 ; Bhati et al, 2021 ), but also the formulation of enzyme mixtures for the performance of synergistic studies ( Wang and Lu, 2016 ).…”

“…Our group has been involved in the research on applications of recombinant cellulases since the mid-1980s. We pioneered the development of various microbial systems and strategies with the aims to: 1) facilitate the cloning and expression of target cellulase genes; 2) provide a competent surrogate host(s) for the expression and/or co-expression of cellulases; 3) achieve enhanced levels of production of cellulases for co-operative studies ( Skipper et al, 1985 ; Wong et al, 1988 ; Lam et al, 1997 ; Lam et al, 1998 ; Fu et al, 2006 ; Wang et al, 2010 ; Wang et al, 2011 ; Chan et al, 2012 ; Wong et al, 2012 ; Kwong et al, 2016a ; Chan et al, 2018 ; Wong et al, 2019 ; Siddique et al, 2021 ). Previously, making use of an enzyme mixture comprising an endoglucanase, CenA, and an exoglucanase, Cex, of C. fimi prepared from a common yeast host, we were able to demonstrate the existence of cooperativity formed between CenA/Cex and a commercial cellobiase preparation in cellulose degradation ( Wong et al, 1988 ).…”

The Cytoplasmic and Periplasmic Expression Levels and Folding of Organophosphorus Hydrolase Enzyme in Escherichia coli

“…Different systems expressing periplasmic OPH in Escherichia coli expression systems have been developed using twin-arginine translocation or sec pathway-driven pathways, involving many advantages including simplified downstream processing, enhanced biological activity, conducting in vivo activity assays due to greater access of the targeted protein to the substrate, higher product stability and solubility, N-terminal authenticity of the expressed protein, simpler and cost effective purification due to a lower protein content compared to the cytoplasm, and providing the oxidative environment required for correct protein folding ( 13 - 15 ). However, the low secretion efficiency, incomplete secretion of recombinant protein, insufficient capacity for secretion of overexpressed recombinant protein, the death of host cells, and proteolytic degradation of the product in E. coli periplasmic expression systems are problematic despite some successful examples ( 16 ). The intracellular production of recombinant proteins in E. coli cytoplasm which is widely used has several advantages over the secretion of recombinant proteins to the periplasm; however, improper folding of many target proteins may occur during this process.…”