Showing papers on "Pichia pastoris published in 2019"
TL;DR: This review is dedicated to discuss on significant characteristics of the most common methylotrophic and non-methylotrophic yeast expression systems with an emphasis on their advantages and new developments.
Abstract: Yeasts are outstanding hosts for the production of functional recombinant proteins with industrial or medical applications. Great attention has been emerged on yeast due to the inherent advantages and new developments in this host cell. For the production of each specific product, the most appropriate expression system should be identified and optimized both on the genetic and fermentation levels, considering the features of the host, vector and expression strategies. Currently, several new systems are commercially available; some of them are private and need licensing. The potential for secretory expression of heterologous proteins in yeast proposed this system as a candidate for the production of complex eukaryotic proteins. The common yeast expression hosts used for recombinant proteins' expression include Saccharomyces cerevisiae, Pichia pastoris, Hansenula polymorpha, Yarrowia lipolytica, Arxula adeninivorans, Kluyveromyces lactis, and Schizosaccharomyces pombe. This review is dedicated to discuss on significant characteristics of the most common methylotrophic and non-methylotrophic yeast expression systems with an emphasis on their advantages and new developments.
101 citations
TL;DR: An overview of protein-based polymers produced in P. pastoris is provided, which includes their physicochemical properties, briefly note possible applications, and detail their biosynthesis.
63 citations
TL;DR: This work focuses on the methanol induction strategies for efficient fed-batch HCDF in bioreactors, mainly focusing on various stat-induction strategies, co-feeding, and the limited induction strategy that are expected to enhance the production of recombinant proteins.
Abstract: Pichia pastoris is extensively used to produce various heterologous proteins. Amounts of biopharmaceutical drugs and industrial enzymes have been successfully produced by fed-batch high-cell-density fermentation (HCDF) of this cell factory. High levels of cell mass in defined media can be easily achieved and therefore large quantities of recombinant proteins with enhanced activities and lower costs can be obtained through HCDF technology. A robust HCDF process makes a successful transition to commercial production. Recently, efforts have been made to increase the heterologous protein production and activity by the HCDF of P. pastoris. However, challenges around selecting a suitable HCDF strategy exist. The high-level expression of a specific protein in P. pastoris is still, at least in part, limited by optimizing the methanol feeding strategy. Here, we review the progress in developments and applications of P. pastoris HCDF strategies for enhanced expression of recombinant proteins. We focus on the methanol induction strategies for efficient fed-batch HCDF in bioreactors, mainly focusing on various stat-induction strategies, co-feeding, and the limited induction strategy. These processes control strategies have opened the door for expressing foreign proteins in P. pastoris and are expected to enhance the production of recombinant proteins.
60 citations
TL;DR: Going beyond the standard approaches employing single heterologous genes or simultaneous expression of several different genes under the control of identical promoter and terminator sequences, balanced and consecutive co-expression of multiple genes combined with simple host genome editing now opens new opportunities for manufacturing of recombinant proteins or chemicals made by whole cell biocatalysis or synthetic biology.
56 citations
TL;DR: A CRISPR–Cas9-mediated multiloci gene integration method was developed with efficient gRNA targets in P. pastoris and is beneficial for pathway assembly of complicated pharmaceuticals and chemicals expressed in the organism.
Abstract: Pichia pastoris (syn. Komagataella phaffii) is a widely used generally recognized as safe host for heterologous expression of proteins in both industry and academia. Recently, it has been shown to be a potentially good chassis host for the production of high-value pharmaceuticals and chemicals. Nevertheless, limited availability of selective markers and low efficiency of homologous recombination make this process difficult and time-consuming, particularly in the case of multistep biosynthetic pathways. Therefore, it is crucial to develop an efficient and marker-free multiloci gene knock-in method in P. pastoris. A non-homologous-end-joining defective strain (Δku70) was first constructed using the CRISPR–Cas9 based gene deficiency approach. It was then used as a parent strain for multiloci gene integration. Ten guide RNA (gRNA) targets were designed within 100 bp upstream of the promoters or downstream of terminator, and then tested using an eGFP reporter and confirmed as suitable single-locus integration sites. Three high-efficiency gRNA targets (PAOX1UP-g2, PTEF1UP-g1, and PFLD1UP-g1) were selected for double- and triple-locus co-integration. The integration efficiency ranged from 57.7 to 70% and 12.5 to 32.1% for double-locus and triple-locus integration, respectively. In addition, biosynthetic pathways of 6-methylsalicylic acid and 3-methylcatechol were successfully assembled using the developed method by one-step integration of functional genes. The desired products were obtained, which further established the effectiveness and applicability of the developed CRISPR–Cas9-mediated gene co-integration method in P. pastoris. A CRISPR–Cas9-mediated multiloci gene integration method was developed with efficient gRNA targets in P. pastoris. Using this method, multiple gene cassettes can be simultaneously integrated into the genome without employing selective markers. The multiloci integration strategy is beneficial for pathway assembly of complicated pharmaceuticals and chemicals expressed in P. pastoris.
55 citations
TL;DR: A single-gene-encoded monomeric IgA protects piglets from enterotoxic E. coli infection in piglets and can be produced in soybean seeds or secreted from the yeast Pichia pastoris.
Abstract: Oral antibodies that interfere with gastrointestinal targets and can be manufactured at scale are needed. Here we show that a single-gene-encoded monomeric immunoglobulin A (IgA)-like antibody, composed of camelid variable single domain antibodies (VHH) fused to IgA Fc (mVHH-IgA), prevents infection by enterotoxigenic Escherichia coli (F4-ETEC) in piglets. The mVHH-IgA can be produced in soybean seeds or secreted from the yeast Pichia pastoris, freeze- or spray-dried and orally delivered within food. A single-gene-encoded monomeric IgA protects piglets from enterotoxic E. coli infection.
45 citations
TL;DR: This review focuses on the motivation for using and producing sweet proteins, the properties and history of thaumatin, the production of recombinantSweet proteins, and future possibilities for process optimization based on a systems biology approach.
Abstract: There is currently a worldwide trend to reduce sugar consumption. This trend is mostly met by the use of artificial non-nutritive sweeteners. However, these sweeteners have also been proven to have adverse health effects such as dizziness, headaches, gastrointestinal issues, and mood changes for aspartame. One of the solutions lies in the commercialization of sweet proteins, which are not associated with adverse health effects. Of these proteins, thaumatin is one of the most studied and most promising alternatives for sugars and artificial sweeteners. Since the natural production of these proteins is often too expensive, biochemical production methods are currently under investigation. With these methods, recombinant DNA technology is used for the production of sweet proteins in a host organism. The most promising host known today is the methylotrophic yeast, Pichia pastoris. This yeast has a tightly regulated methanol-induced promotor, allowing a good control over the recombinant protein production. Great efforts have been undertaken for improving the yields and purities of thaumatin productions, but a further optimization is still desired. This review focuses on (i) the motivation for using and producing sweet proteins, (ii) the properties and history of thaumatin, (iii) the production of recombinant sweet proteins, and (iv) future possibilities for process optimization based on a systems biology approach.
43 citations
TL;DR: The active center and substrate binding pocket of the recombinant Chit46 (rChit46) were analyzed and the effects of pH, temperature, metal ions and glycosylation on its activity were tested.
43 citations
TL;DR: The bottlenecks and solutions in achieving high‐level secretory protein expression with P. pastoris are summarized and its applications on chemical production with an emphasis on its role as whole‐cell biocatalyst are outlined.
Abstract: With nearly three decades of development, Pichia pastoris (P. pastoris) has become a powerful eukaryotic protein expression system for the expression of thousands of proteins both on a laboratory and industrial scale. In addition, it has also been extensively used as a cell factory for the production of a variety of chemicals. This review summarizes the bottlenecks and solutions in achieving high-level secretory protein expression with P. pastoris and then outlines its applications on chemical production with an emphasis on its role as whole-cell biocatalyst. Furthermore, current challenges and future directions of this important system are also discussed.
39 citations
TL;DR: This is the first report about d-lactic acid production from methanol by an engineered P. pastoris strain and the technique of gene integration into the rDNA locus and post-transformational gene amplification could be useful for metabolic engineering in P. pastors.
Abstract: With the reduction in oil reserves and steady increases in the price of oil, alternative carbon sources like methanol are promising, but an efficient conversion process to fuels and other chemicals is still desired. In this study, we demonstrated for the first time the production of lactic acid from methanol using a lactate dehydrogenase copy number amplifying strategy in Pichia pastoris. We engineered methylotrophic yeast (Pichia pastoris) producing D-lactic acid by D-lactate dehydrogenase gene (d-LDH) integration into the non-transcribed spacer of the ribosomal DNA (rDNA) locus and post-transformational amplification. The resultant engineered strains GS115/S8/Z3 and GS115/S16/Z3 produced 3.48 and 3.26 g/L of D-lactic acid from methanol, respectively, in a 96-h test tube fermentation. To our knowledge, this is the first report about D-lactic acid production from methanol by an engineered P. pastoris strain. The technique of gene integration into the rDNA locus and post-transformational gene amplification could be useful for metabolic engineering in P. pastoris, and the chemical production from methanol by engineered P. pastoris represents a promising industrial technology.
34 citations
TL;DR: It is demonstrated that plant mannan and glucomannan can be synthesized heterologously in the yeast Pichia pastoris, and the polysaccharide’s structure can be modulated by specific plant cofactors, allowing for the synthesis of tailored mannan structures.
Abstract: Heteromannan (HM) is one of the most ancient cell wall polymers in the plant kingdom, consisting of β-(1–4)-linked backbones of glucose (Glc) and mannose (Man) units. Despite the widespread distribution of HM polysaccharides, their biosynthesis remains mechanistically unclear. HM is elongated by glycosyltransferases (GTs) from the cellulose synthase-like A (CSLA) family. MANNAN-SYNTHESIS RELATED (MSR) putative GTs have also been implicated in (gluco)mannan synthesis, but their roles have been difficult to decipher in planta and in vitro. To further characterize the products of the HM synthases and accessory proteins, we chose a synthetic biology approach to synthesize plant HM in yeast. The expression of a CSLA protein in Pichia pastoris led to the abundant production of plant HM: up to 30% of glycans in the yeast cell wall. Based on sequential chemical and enzymatic extractions, followed by detailed structural analyses, the newly produced HM polymers were unbranched and could be larger than 270 kDa. Using CSLAs from different species, we programmed yeast cells to produce an HM backbone composed exclusively of Man or also incorporating Glc. We demonstrate that specific MSR cofactors were indispensable for mannan synthase activity of a coffee CSLA or modulated a functional CSLA enzyme to produce glucomannan instead of mannan. Therefore, this powerful platform yields functional insight into the molecular machinery required for HM biosynthesis in plants.
TL;DR: A CRISPR/Cas9-based kit for gene insertions, deletions, and replacements, which paves the way for precise genomic modifications in P. pastoris without the integration of a selection marker is developed.
Abstract: State-of-the-art strain engineering techniques for the methylotrophic yeast Pichia pastoris (syn. Komagataella spp.) include overexpression of endogenous and heterologous genes and deletion of host genes. For efficient gene deletion, methods such as the split-marker technique have been established. However, synthetic biology trends move toward building up large and complex reaction networks, which often require endogenous gene knockouts and simultaneous overexpression of individual genes or whole pathways. Realization of such engineering tasks by conventional approaches employing subsequent steps of transformations and marker recycling is very time- and labor-consuming. Other applications require tagging of certain genes/proteins or promoter exchange approaches, which are hard to design and construct with conventional methods. Therefore, efficient systems are required that allow precise manipulations of the P. pastoris genome, including simultaneous overexpression of multiple genes. To meet this challenge, we have developed a CRISPR/Cas9-based kit for gene insertions, deletions, and replacements, which paves the way for precise genomic modifications in P. pastoris. In this chapter, the versatile method for performing these modifications without the integration of a selection marker is described. A ready-to-use plasmid kit for performing CRISPR/Cas9-mediated genome editing in P. pastoris based on the GoldenPiCS modular cloning vectors is available at Addgene as CRISPi kit (#1000000136).
TL;DR: Results indicate that Hispidalin could be produced on a large scale by P. pastoris and has a great potential to be utilized as a new antibacterial agent for further development.
TL;DR: Results showed that the hardness, chewiness, and F1 of the restructured pork increased, and the adhesiveness decreased after MTG treatment, However, high temperature had greater effect on the texture of restructured Pork afterMTG treatment than that of the control.
TL;DR: Extracellular pectinase activity was found in three yeast and yeast-like microorganisms from which the highest activity was displayed by Tetracladium sp.
Abstract: Pectinolytic enzymes, which are used in several industries, especially in the clarification process during wine and fruit juice production, represent approximately 10% of the global enzyme market. To prevent the proliferation of undesired microorganisms, to retain labile and volatile flavor compounds, and to save energy, the current trend is to perform this process at low temperatures. However, the commercially available pectinases are highly active at temperatures approximately 50 °C and poorly active at temperatures below 35 °C, which is the reason why there is a constant search for cold-active pectinases. In preliminary studies, pectinolytic activity was detected in cold-adapted yeasts and yeast-like microorganisms isolated from Antarctica. The aim of the present work was to characterize pectinases secreted by these microorganisms and to express the best candidate in Pichia pastoris. Degradation of pectin by extracellular protein extracellular extracts obtained from 12 yeast cultures were assayed in plates at 4 °C to 37 °C and pH from 5.4 to 7.0, obtaining positive results in samples obtained from Dioszegia sp., Phenoliferia glacialis and Tetracladium sp. An enzyme was purified from Tetracladium sp., analyzed by peptide mass fingerprinting and compared to genome and transcriptome data from the same microorganism. Thus, the encoding gene was identified corresponding to a polygalacturonase-encoding gene. The enzyme was expressed in Pichia pastoris, and the recombinant polygalacturonase displayed higher activity at 15 °C than a mesophilic counterpart. Extracellular pectinase activity was found in three yeast and yeast-like microorganisms from which the highest activity was displayed by Tetracladium sp., and the enzyme was identified as a polygalacturonase. The recombinant polygalacturonase produced in P. pastoris showed high activity at 15 °C, representing an attractive candidate to be applied in clarification processes in the production of fermented beverages and fruit juices.
TL;DR: Improved production of xylanase increases fluorescence intensity of gel microdroplets, enabled accurate selection of evolved clones by droplet sorting, and greatly shortened incubation time prior screening significantly accelerated the process of directed evolution.
TL;DR: A novel α-amylase gene (TdAmyA) with an open reading frame of 1431 bp, deducing 476 amino acids, was cloned from the thermophilic fungus Thermomyces dupontii L18 and might be a candidate α-Amylase for maltose syrup production.
TL;DR: The improved activity and stability in alkaline pH of rLcc9 relative to Lcc9, and improved dye decolorization ability towards 6 dyes suggested greater application potential of r laccase in biotechnologies such as wastewater treatment.
TL;DR: The data collected suggest that the role of the WSC domain of PoAlcOX is not recognition of substrates but attaching the enzyme to plant and/or fungal cell wall, and the carbohydrate-binding property of the domain is demonstrated.
TL;DR: This review focuses on understanding the key factors that can enhance recombinant protein production in Pichia pastoris; they are the basis for a further discussion on future industrial applications with the aim of developing scalable alternative strategies that maximize yields and productivity.
TL;DR: The results demonstrated that the expression level of the thermostable YlLip2 mutant was predominantly enhanced via the combination of these strategies in P. pastoris, which forms a consolidated basis for its large-scale production and future industrial applications.
Abstract: As a promising biocatalyst, Yarrowia lipolytica lipase 2 (YlLip2) is limited in its industrial applications due to its low thermostability. In this study, a thermostable YlLip2 mutant was overexpressed in Pichia pastoris and its half-life time was over 30 min at 80 °C. To obtain a higher protein secretion level, the gene dosage of the mutated lip2 gene was optimized and the lipase activity was improved by about 89%. Then, the YlLip2 activity of the obtained strain further increased from 482 to 1465 U/mL via optimizing the shaking flask culture conditions. Subsequently, Hac1p and Vitreoscilla hemoglobin (VHb) were coexpressed with the YlLip2 mutant to reduce the endoplasmic reticulum stress and enhance the oxygen uptake efficiency in the recombinant strains, respectively. Furthermore, high-density fermentations were performed in a 3 L bioreactor and the production of the YlLip2 mutant reached 9080 U/mL. The results demonstrated that the expression level of the thermostable YlLip2 mutant was predominantly enhanced via the combination of these strategies in P. pastoris, which forms a consolidated basis for its large-scale production and future industrial applications.
TL;DR: Large-scale production of rHBsAg in recombinant P. pastoris, using the chemostat operation mode is more cost-effective and time-sparing than the conventional fed-batch production system.
TL;DR: The cloning, heterologous expression, purification and characterization of a novel LMCO from the thermophilic fungus Thermothelomyces thermophila, presenting a number of superior properties with potential use in industrial biocatalysis.
TL;DR: These novel signal peptides and folding factors can be used for promoting secretion of heterologous proteins in P. pastoris and exhibited a protein-specific effect on cell growth, transcription and expression of different reporter genes.
TL;DR: The regulation mechanisms of inducible pAOX1 and constitutive pGAP promoters are discussed and an overview about the novel ADH3 promoter and alternative promoters of P. pastoris is presented.
Abstract: The methylotrophic yeast Pichia pastoris (Komagataella phaffii) is used as an expression system for recombinant protein production for a variety of applications. It grows rapidly on inexpensive media containing methanol, glucose, glycerol, or ethanol as a sole carbon source. P. pastoris makes many posttranslational modifications and produces recombinant proteins either intracellularly or extracellularly. Because of these properties, P. pastoris has become a highly preferred host organism for biotechnology, pharmaceutical industry, and researchers.Recombinant protein production is usually performed under the control of the promoter of the alcohol oxidase gene I (AOX1). The AOX1 promoter is induced by methanol and repressed by glucose and ethanol. The regulation mechanisms of the AOX1 promoter have been studied in recent years. Another promoter used in recombinant protein production is derived from glyceraldehyde 3-phosphate dehydrogenase (GAP). It is a constitutive promoter. Recent literature showed that newly identified promoters of P. pastoris are promising as well, in addition to pAOX1 and pGAP.In this chapter, the regulation mechanisms of inducible pAOX1 and constitutive pGAP promoters are discussed. In addition, here we present an overview about the novel ADH3 promoter and alternative promoters of P. pastoris.
TL;DR: This study aims to improve on the characterization of a thermostable Aspergillus fumigatus endo-1,4-β-glucanase GH7 (Af-EGL7), which was successfully expressed in Pichia pastoris X-33 and was tolerant to inhibition by products, such as glucose and cellobiose.
Abstract: In the context of avoiding the use of non-renewable energy sources, employing lignocellulosic biomass for ethanol production remains a challenge. Cellulases play an important role in this scenario: they are some of the most important industrial enzymes that can hydrolyze lignocellulose. This study aims to improve on the characterization of a thermostable Aspergillus fumigatus endo-1,4-β-glucanase GH7 (Af-EGL7). To this end, Af-EGL7 was successfully expressed in Pichia pastoris X-33. The kinetic parameters Km and Vmax were estimated and suggested a robust enzyme. The recombinant protein was highly stable within an extreme pH range (3.0–8.0) and was highly thermostable at 55 °C for 72 h. Low Cu2+ concentrations (0.1–1.0 mM) stimulated Af-EGL7 activity up to 117%. Af-EGL7 was tolerant to inhibition by products, such as glucose and cellobiose. Glucose at 50 mM did not inhibit Af-EGL7 activity, whereas 50 mM cellobiose inhibited Af-EGL7 activity by just 35%. Additionally, the Celluclast® 1.5L cocktail supplemented with Af-EGL7 provided improved hydrolysis of sugarcane bagasse “in natura”, sugarcane exploded bagasse (SEB), corncob, rice straw, and bean straw. In conclusion, the novel characterization of Af-EGL7 conducted in this study highlights the extraordinary properties that make Af-EGL7 a promising candidate for industrial applications.
TL;DR: Investigation of the inhibitory effect of wheat β-1,3-glucanase on fungi most commonly associated with wheat kernel to help elucidate the mechanism underlying the inhibition of wheatβ-1-3- glucanases on pathogens.
TL;DR: Molecular dynamic simulations confirmed the sharing of common amino acid residues conserved for catalysis of both cellulosic and hemicellulosic substrates which further indicates that both substrates are equally preferred.
TL;DR: Fusion expression with three fusion partners was investigated to enhance the expression level of an acidic lipase from A. niger in Pichia pastoris, and named SANL, which was resistant to pepsin and had high hydrolytic activity against triolein in gastrointestinal digestion experiments.
TL;DR: Owing to the higher plasmid stability with panARS, efficient CRISPR/Cas9-mediated genome editing with a type III promoter to drive the expression of the single guide RNA (sgRNA) was achieved for the first time.
Abstract: The methylotrophic yeast Pichia pastoris is widely used in recombinant expression of eukaryotic proteins owing to the ability of post-translational modification, tightly regulated promoters, and high cell density fermentation. However, episomal plasmids for heterologous gene expression and the CRISPR/Cas9 system for genome editing have not been well developed in P. pastoris. In the present study, a panel of episomal plasmids containing various autonomously replicating sequences (ARSs) were constructed and their performance in transformation efficiency, copy numbers, and propagation stability were systematically compared. Among the five ARSs with different origins, panARS isolated from Kluyveromyces lactis was determined to have the best performance and used to develop an efficient CRISPR/Cas9 based genome editing system. Compared with a previously reported system using the endogenous and most commonly used ARS (PARS1), the CRISPR/Cas9 genome editing efficiency was increased for more than tenfold. Owing to the higher plasmid stability with panARS, efficient CRISPR/Cas9-mediated genome editing with a type III promoter (i.e. SER promoter) to drive the expression of the single guide RNA (sgRNA) was achieved for the first time. The constructed episomal plasmids and developed CRISPR/Cas9 system will be important synthetic biology tools for both fundamental studies and industrial applications of P. pastoris.