A novel maltose (G2)-forming α-amylase from Lactobacillus plantarum subsp. plantarum ST-III was expressed in Escherichia coli and characterized. Analysis of conserved amino acid sequence alignments showed that L. plantarum maltose-producing α-amylase (LpMA) belongs to glycoside hydrolase family 13. The recombinant enzyme (LpMA) was a novel G2-producing α-amylase. The properties of purified LpMA were investigated following enzyme purification. LpMA exhibited optimal activity at 30 °C and pH 3.0. It produced only G2 from the hydrolysis of various substrates, including maltotriose (G3), maltopentaose (G5), maltosyl β-cyclodextrin (G2-β-CD), amylose, amylopectin, and starch. However, LpMA was unable to hydrolyze cyclodextrins. Reaction pattern analysis using 4-nitrophenyl-α-d-maltopentaoside (pNPG5) demonstrated that LpMA hydrolyzed pNPG5 from the nonreducing end, indicating that LpMA is an exotype α-amylase. Kinetic analysis revealed that LpMA had the highest catalytic efficiency (kcat/Km ratio) toward G2-β-CD. Compared with β-amylase, a well-known G2-producing enzyme, LpMA produced G2 more efficiently from liquefied corn starch due to its ability to hydrolyze G3.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.jafc.5b05892 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Antifungal Associations with a Polyelectrolyte Promote Significant Reduction of Minimum Inhibitory Concentrations against Opportunistic Candida spp. Strains.
Curr Microbiol
November 2024
Laboratório de Pesquisa Em Micologia Aplicada (LPMA), Universidade Federal Do Rio Grande Do Sul, Rua São Luís 152, Porto Alegre, 90470-440, Brazil.
The current global scenario presents us with a growing increase in infections caused by fungi, referred to by specialists in the field as a "silent epidemic", aggravated by the limited pharmacological arsenal and increasing resistance to this therapy. For this reason, drug repositioning and therapeutic compound combinations are promising strategies to mitigate this serious problem. In this context, this study investigates the antifungal activity of the non-toxic, low-cost and widely available cationic polyelectrolyte Poly(diallyldimethylammonium chloride) (PDDA), in combination with different antifungal drugs: systemic (amphotericin B, AMB), topical (clioquinol, CLIO) and oral (nitroxoline, NTX).
View Article and Find Full Text PDF3D Printable Alginate-Chitosan Hydrogel Loaded With Ketoconazole Exhibits Anticryptococcal Activity.
Biopolymers
January 2025
Laboratório de Biomateriais Poliméricos (Poli-BIO), Instituto de Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Natural polymers have recently been investigated for various applications, such as 3D printing and healthcare, including treating infections. Among microbial infections, fungal diseases remain overlooked, with limited therapeutic options and high recurrence. Cutaneous cryptococcosis is an opportunistic fungal infection triggered by mechanical inoculation or hematogenous dissemination of the yeast that causes cryptococcal pneumonia and meningitis.
View Article and Find Full Text PDFMechanisms of horizontal gene transfer and viral contribution to the fate of intracellular and extracellular antibiotic resistance genes in anaerobic digestion supplemented with conductive materials under ammonia stress.
Water Res
December 2024
Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai, 200062, China. Electronic address:
The addition of conductive materials (CMs) is an effective strategy for mitigating ammonia inhibition during anaerobic digestion (AD). However, the introduction of CMs can result in increased antibiotic resistance genes (ARGs) pollution, potentially facilitated by enhanced horizontal gene transfer (HGT). The complex dynamics of intracellular and extracellular ARGs (iARGs/eARGs) and the mechanisms underlying their transfer, mediated by CMs, in ammonia-stressed AD systems remain unclear.
View Article and Find Full Text PDFNeglected risks of enhanced antimicrobial resistance and pathogenicity in anaerobic digestion during transition from thermophilic to mesophilic.
J Hazard Mater
August 2024
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
Minimization of antibiotic resistance genes (ARGs) and potential pathogenic antibiotic-resistant bacteria (PARB) during anaerobic digestion (AD) is significantly impacted by temperature. However, knowledge on how ARGs and PARB respond to temperature transition from thermophilic to mesophilic is limited. Here, we combined metagenomic-based with culture-based approaches and revealed the risks of antimicrobial resistance and pathogenicity during transition from 55 °C to 35 °C for AD, with strategies of sharp (ST, one-step by 20 °C/d) and mild (MT, step-wise by 1 °C/d).
View Article and Find Full Text PDFFunctional traits and health implications of the global household drinking-water microbiome retrieved using an integrative genome-centric approach.
Water Res
February 2024
School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai 200062, PR China. Electronic address:
The biological safety of drinking water plays a crucial role in public health protection. However, research on the drinking water microbiome remains in its infancy, especially little is known about the potentially pathogenic bacteria in and functional characteristics of the microbiome in household tap water that people are directly exposed to. In this study, we used a genomic-centric approach to construct a genetic catalogue of the drinking water microbiome by analysing 116 metagenomic datasets of household tap water worldwide, spanning nine countries/regions on five continents.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!