Critical Reviews in Biotechnology最新文献

β-glucosidases are a well-characterized, diverse group of hydrolytic enzymes that act on various substrates. They are extensively used in different sectors, including: bioethanol, food, flavor, nutraceutical, and pharmaceutical industries. Immobilization improves the operational stability, reusability and catalytic efficiency of β-glucosidase compared to the free enzyme. The nanoscale dimensions, high surface area of the nanomaterial, and strong enzyme-nanosupport interactions prevent denaturation and leaching of β-glucosidase. This boosts enzyme stability, reduces the need for replenishment, and allows for easy recovery and reuse, minimizing enzyme waste and energy consumption in industrial biocatalysis. Nanosupport materials, including: inorganic materials, carbon, biopolymer-based, and magnetic nanoparticles, have gained popularity as immobilization matrices for generating either β-glucosidase immobilization or co-immobilization systems for various applications. The present review focuses on the current trends in immobilization strategies of β-glucosidase for improving operational stability and recyclability of the enzyme. Additionally, this review provides deeper insights into various surface modifications of magnetic and non-magnetic nanosupport matrices employed for immobilization and their impact on the catalytic efficiency of β-glucosidase. Moreover, the review thoroughly investigates the challenges encountered in immobilizing β-glucosidases on various nanosupport matrices. It concludes with insightful remarks that encourage future researchers to conduct studies dedicated to the development of a highly efficient, industrially adapted nanobiocatalytic system to achieve sustainable biotransformation aligning with United Nations Sustainable Development Goals (SDG): SDG 2 (Sustainable Food System), SDG 7 (Affordable and Clean Energy), SDG 9 (Sustainable Industry), SDG 12 (Responsible Consumption), and SDG 13 (Climate Action: Reducing Carbon Emissions).

Antimicrobial peptides (AMPs) play a crucial defensive role in living organisms, capable of rapidly responding to and eliminating invading microorganisms. Their mechanisms of action are diverse, primarily involving the disruption of microbial cell membranes. The interest in AMPs stems from their potential to address antibiotic resistance and improve human health. AMPs exhibit: broad-spectrum antimicrobial activity, low toxicity, thermal stability, and high specificity, making them promising candidates for new antimicrobial drugs with applications in medicine, food preservation, and agriculture. This review provides a comprehensive summary of the historical development and classification of AMPs. It details their: classification, mechanisms of action, application fields, and processes involved in the isolation, purification, and structural identification of microbial-derived AMPs. Additionally, it introduces a novel green extraction method using deep eutectic solvents (DESs) for peptide extraction.

Viral outbreaks are a topic of worldwide concern, resulting in a significant impact in health systems, a large number of deaths, and huge economical losses. The damage caused by Covid-19 has further highlighted the importance of prospecting for new molecules that can be applied in the prevention and treatment of viral infections. Many studies describe the remarkable antimicrobial activity of lipopeptides produced by Bacillus spp., especially against fungi and bacteria. However, research regarding the antagonistic effects on viruses is less frequent. Despite that, the antiviral activity of lipopeptides produced by Bacillus spp. has been demonstrated, indicating that these molecules could be potential candidates to control viral diseases. In this article, a compilation of reports with consistent data regarding the antiviral effect of Bacillus lipopeptides and the mechanisms involved in this process are presented. Moreover, the immunomodulatory role and toxicity profile of these molecules are discussed. Bacillus lipopeptides may exert an indirect antiviral effect, since they are able to positively induce humoral and cell-mediated immune responses. Moreover, their antiviral effect was observed in vitro and in vivo at nontoxic concentrations, offering a safe perspective for possible clinical application of these molecules. Finally, the challenges related to optimization and increasing production yield are addressed. This is the first critical review dedicated exclusively to antiviral activity of Bacillus lipopeptides.

Bacterial extracellular vesicles (EVs) are produced by both Gram-negative and Gram-positive bacteria. These EVs are composed of lipid bilayers and various components derived from parent bacteria, including proteins, lipids, and nucleic acids. Previous studies have indicated the significant role of bacterial EVs in interactions between bacteria and between bacteria and hosts. Moreover, bacterial EVs are emerging as promising delivery vectors capable of transporting drug molecules over long distances to tissues. Therefore, understanding the biogenesis of bacterial EVs and how to regulate their production holds great importance for expanding their applications. In this review, we provide an overview of bacterial EVs, especially focusing on the distinct mechanisms of EVs biogenesis and the regulation of EVs production in both Gram-negative and Gram-positive bacteria. Additionally, we discuss various methods for cargos loading into bacteria EVs, as well as their diverse applications in vaccines, cancer therapy, and drug delivery. We anticipate that this review will advance the field of bacterial EVs, contributing to both the enhancement of existing applications and the emergence of novel applications.

The rise of chronic and acute infections has increased reliance on antimicrobial agents. However, conventional antimicrobials often fail to deliver optimal therapeutic outcomes due to limitations such as low bioavailability, poor biocompatibility, nonspecific targeting, drug-induced toxicity, and the growing issue of antimicrobial resistance. Therefore, the concept of a resistance-proof antimicrobial agent (RPAA) and its smart delivery was introduced to overcome the existing problem and a targeted delivery due to the specific properties, such as: high bioavailability, biocompatibility, low drug-induced toxicity, biodegradability, high binding capacity with the pathogen, multiple targeting delivery, etc. This system generates a positive impact and could quash the multidrug resistance problem. In this review, we discuss: the rationale for developing a nanoengineering-based smart-delivery system for RPAA, the advantageous properties of such a system, the possible mechanism of delivery, and challenges in the development of a nano-drug delivery therapeutics tool for RPAA delivery as a solution to combat the global problem of drug resistance. We emphasize the urgent need for the development of such a next-generation drug delivery system and discuss the opportunities/hurdles as well as the questions that remain to be addressed. The article is important because it sheds light on the properties of nanoengineered drug delivery that could initiate new ways of thinking about the development of future-generation delivery systems. The article shares a promising idea that would be an essential foundation for opening a new window in the field of drug discovery and development of the smart delivery system for RPAA.

Upon pathogen attack, cytosolic Ca²⁺ levels increase in plant cells. The first innate immune response is activated by detecting microbe/pathogen-associated molecular patterns (MAMPs/PAMPs) and is called PAMPs-triggered immunity (PTI). The second immune response is triggered by recognizing pathogens' effector proteins named effectors-triggered immunity (ETI). Calcium-dependent protein kinases (CDPKs or CPKs) are well-known calcium sensors that have a mediator role both in PTI and ETI. Calcium can bind to the elongation factor (EF)-hand domain at the C-terminus of CDPKs, which then phosphorylates substrates at the N-terminal catalytic kinase domain to transfer calcium signals directly. Improving the stress resilience of crops is a critical strategy in attaining global food security. In plants, when a stimulus is seen, there is an increase in Ca²⁺ concentration, which activates CDPKs which are in charge of sending out the immunological signals needed for disease tolerance. During the immune response, CDPKs are subject to numerous levels of regulation, including Ca²⁺ dependency to decipher various Ca²⁺ signals. Furthermore, salicylic acid (SA) regulation by CDPKs provides a comprehensive overview of CDPKs-mediated SA signaling during immune response in plants under pathogen attack. The critical part of CDPKs in SA biosynthesis, from the regulation of SA biosynthesis to how NPR1 perceives SA upon biotic stress, is comprehensively reviewed in this paper with the latest advancements in research. However, more research about CDPKs-mediated SA signaling under pathogen attack is mandatory to further dissect their co-role in crop protection against various diseases to achieve sustainable production goals in the future.

Global warming caused by CO₂ emissions has been considered as one of the major challenges of this century. In an endeavor to control and reduce CO₂ emissions, a series of Carbon dioxide Capture, Utilization, and Storage (CCUS) technologies have been developed specifically for the sequestration of CO₂ from atmospheric air. Microalgae, as versatile and universal photosynthetic microorganisms, represent a promising avenue for biological CO₂ sequestration. Nevertheless, further advancements are necessary to optimize microalgae-based carbon sequestration technology in terms of light reaction and dark reaction. This review discusses the current status of microalgae-based artificial CO₂ sequestration technique, with a particular focus on the selection of CO₂-resistant species, optimization of cultivation for CO₂ sequestration, design of carbon concentration reactor, and the potential of synthetic biology to enhance CO₂ solubility and biofixation efficiency. Furthermore, a discussion of Life cycle assessment and Techno-economic analysis regarding microalgae-based carbon capture was performed. The aim of this comprehensive review is to stimulate further research into microalgae-based CO₂ sequestration, addressing challenges and opportunities for future development.

Reporter systems are gaining increasing popularity in modern molecular biology as they provide reliable and clear readouts for various types of assays, both in cellulo and in vivo. The generation of reporter cell lines is instrumental for screening activators and inhibitors of signaling pathways to develop new therapeutic approaches. Reporter cell lines are those with stably integrated reporter constructs containing signaling genes (often luciferase or fluorescent proteins), enabling the visualization and tracking of protein expression. Although seemingly harmless and straightforward, untargeted genomic integration of reporter genes may severely affect the expression of neighboring genes, causing unwanted and unpredictable effects. Unlike the untargeted approach, the CRISPR/Cas9 system provides a more precise method of reporter integration, especially when reporters are integrated into Safe Harbor loci. This ensures minimal influence on neighboring genomic regions. This review discusses recent advancements in creating reporter lines using the CRISPR/Cas9 system and experimental approaches for identifying suitable Safe Harbor loci.

A large amount of fruit and vegetable waste is generated after harvest, during processing from the food industry and along the supply chain due to fresh produce quality deterioration. Fruit and vegetable waste may impact various sectors, such as the environment, economy, and society. In the last two decades, several studies have tried to mitigate the impact of fruit and vegetable waste by developing and optimizing extraction methods, targeting specific compounds without considering the value and further utilization of the remaining wet residue. Recently, biorefinery systems have been explored and developed for the holistic valorization of fruit and vegetable waste. The current research aims to summarize recent studies examining the valorization of different fruit and vegetable by-products using a holistic biorefinery approach. The various steps in a biorefinery process are presented and discussed. Biorefinery systems should be chosen and developed considering the presence or absence of fat-soluble compounds (i.e., oils) in fruit and vegetable waste. In the current study, different biorefinery systems are proposed based on fruit and vegetable waste composition. In conclusion, the phytochemicals and products produced during the biorefinery process can benefit various industries, such as: the food, pharmaceutical, cosmetics, transportation, chemical, heating, agricultural, and horticultural industries. Future multidisciplinary studies are encouraged to investigate the techno-economic and environmental impacts of the biorefinery processes.

The increasing knowledge of the makeup and role of organ microbiomes has created new possibilities for understanding and managing human illnesses. The models used for animal studies conducted in laboratory settings and live animals may not always offer the necessary insights. One in vitro cell culture system known as organ-on-a-chip technology has garnered interest as a way to collect data that accurately reflects human responses. Organ-on-a-chip (OoC) technology, while accurately simulating the function of tissues and organs, has largely covered the differences between animal and human systems. Microbiome-on-a-chip (MoC) offers benefits over other in vitro procedures, permitting dimensional observation of ecological dynamics, microbial growth, and host-associated interactions while regulating and assessing relevant environmental parameters such as pH and O₂ in real-time. The fabricated MoC platforms can be designed to test microbiome-enabled therapies, to study culture and pharmacology, antibiotic resistance, and to model multi-organ interactions mediated by the microbiome. In the current overview, we provide a translational perspective and discuss different organs, such as: oral, skin, gut and vaginal microbiota on a chip and recently developed MoC-based devices. The commonly used MoC fabrication methods, such as microfluidics and 3D printing, have been explored, and the potential applications of MoC in microbiome engineering have been suggested.