Bioscience, Biotechnology, and Biochemistry最新文献

The oleaginous yeast Lipomyces starkeyi has a high capacity for starch assimilation, but the genes involved and specific mechanisms in starch degradation remain unclear. This study aimed to identify the critical carbohydrate-active enzyme (CAZyme) genes contributing to starch degradation in L. starkeyi. Comparative transcriptome analysis of cells cultured in glucose and soluble starch medium revealed that 55 CAZymes (including transcript IDs 3772, 1803, and 7314) were highly expressed in soluble starch medium. Protein domain structure and disruption mutant analyses revealed that 3772 encodes the sole secreted α-amylase (LsAmy1p), whereas 1803 and 7314 encode secreted α-glucosidase (LsAgd1p and LsAgd2p, respectively). Triple-gene disruption exhibited severely impaired growth in soluble starch, dextrin, and raw starch media, highlighting their critical role in degrading polysaccharides composed of glucose linked by α-1,4-glucosidic bonds. This study provided insights into the complex starch degradation mechanism in L. starkeyi.

Recently, non-invasive hemoglobin measurement (SpHb) using Pulse CO-Oximeter Rad-67™ Spot-check (Rad-67) has been validated although anemia diagnosis typically relies on blood hemoglobin concentration measurement. In this large-scale survey of Japanese children aged 1-5 years, we evaluated SpHb distribution to understand the prevalence of suspected anemia, and further examined the relationship between SpHb and background factors. Children were recruited from large retail stores in Japan between November 2022 and August 2023. SpHb was measured by nutritionists or registered dietitians using Rad-67. 4133 participants were included and stratified by age and sex. The prevalence of children below the WHO threshold value for anemia was found to be 5.2% in total (ranging between 2.6-7.8% in subgroups). Mean SpHb values increased with age, and were higher in boys. Age and sex were independently related to SpHb. Overall, this study shows that approximately 3-8% of young children in Japan are suspected to be anemic.

Sphingolipids (SLs), found in all animals, plants, and fungi and in certain prokaryotic organisms, exhibit essential physiological functions that cannot be replicated by other lipids. Although SLs and their related biomolecules behave as lipid mediators, skin barrier systems and epitopes, their detailed biological functions have not yet been revealed, unlike those of proteins and nucleic acids, because the biosynthesis of SLs is not governed by the central dogma. Recently, SLs have been widely studied in relation to diseases such as obesity, dementia, and neuron agenesis and have attracted attention as molecules related to unmet medical needs. This review presents the recent applications of the SL chemical biology in unmet medical needs.

This study aimed to evaluate the suitability of alginate gels, specifically ferric-ion-cross-linked alginate (Fe-alginate) and calcium-ion-cross-linked alginate (Ca-alginate), as scaffolds for soil microbial attachment and biofilm formation in soil. Staining with crystal violet and observations with scanning electron microscopy showed that microorganisms formed biofilms on Fe-alginate surfaces in the soil. When the soil was incubated with Fe-alginate, microbial biomass, estimated by adenosine triphosphate content, increased not only in the Fe-alginate but also in the surrounding soil. The weight of Ca-alginate in the soil decreased with time owing to chemical dissolution. However, the weight of Fe-alginate in the soil did not decrease, likely because it was protected by the microbial biofilm that formed on its surface. These results demonstrate that the use of Fe-alginate, in contrast to Ca-alginate, as a scaffold may allow for more efficient use of soil microbial functions in agriculture and bioremediation.

Coenzyme Q (CoQ), a component of the electron transport chain, participates in aerobic respiration to produce ATP. Little is known about the relationship between CoQ and ethanol fermentation. Herein, we revealed that the deficiency or the addition of CoQ in sake yeast led to an increase or a decrease, respectively, in ethanol production rate at the early stage of fermentation.

Plant growth is finely tuned by environmental changes, with abscisic acid (ABA) playing a key role in balancing stress tolerance and growth regulation. The target genes of MYB50, which regulate root growth, include genes that respond to ABA; however, the precise role of MYB50 in ABA signaling remains unclear. Therefore, this study aimed to elucidate the function of MYB50 under ABA signaling. Our experiments demonstrated that ABA treatment reduced MYB50 expression and promoted the degradation of MYB50 protein. This degradation alleviates the inhibitory effects of MYB50 on root growth. Furthermore, ABA differentially regulates MYB50 compared with ABI5, another key transcription factor involved in root growth under ABA signaling, suggesting that ABA uses distinct regulatory pathways for root growth. Our study suggests that ABA controls root growth by modulating MYB50 at both the transcriptional and post-translational levels, thus ensuring balanced root development in response to ABA.

In this study, we screened 308 lactic acid bacteria strains for high immunoglobulin A (IgA) production, dendritic cell activation, and IL-12 production using human derived cells. Among them, Lactobacillus helveticus GCL1815 demonstrated superior performance in all aspects, indicating its remarkable potential for immunomodulatory functions in both innate and adaptive immunity.

Cloning of small DNA segments has been established using Escherichia coli plasmids. The cloned DNA can be transferred to various cells using transformation. In contrast, cloning of large DNA segments of more than several hundred kilobase pairs has been limited to the Bacillus subtilis genome cloning system. The advantage of giant DNA cloned by B. subtilis is that all kinds of gene editing can be implemented by the high and strict natural transformation ability of the host. However, the following transfer step of giant synthesized and edited genomes to different cell systems require a special system by avoiding exposure in liquid. The use of a conjugational plasmid pLS20 that was developed for 20 years improves the B. subtilis genome vector establishment process from scratch. The use of the unique B. subtilis genome vector system from synthesis to transmit genomes is now being manipulated and summarized for the first time.

The nematode Caenorhabditis elegans is an excellent model organism for elucidating higher life phenomena. C. elegans and humans are common in many aspects. During our research on development and life span regulation, we identified RAB-18, a small GTPase involved in the membrane trafficking of NCR-1, a cholesterol transporter mainly expressed in the intestine. We expressed the human NPC1L1, an intestinal cholesterol transporter, in mutant C. elegans lacking NCR-1. NPC1L1-expressing animals revealed almost the same larval diapause in the presence of a diapause-inducing pheromone and lipid droplets containing cholesterol as in wild-type C. elegans. This result indicates that C. elegans NCR-1 and human NPC1L1 are exchangeable and that C. elegans RAB-18 transports human NPC1L1 to the apical membrane in the C. elegans intestine. This transgenic C. elegans could be adapted to evaluate functional foods and ingredients regarding cholesterol absorption.

Rice panicle architecture exhibits remarkable diversity and is crucial in determining grain production. Recent advances in the understanding of the genetic mechanisms underlying panicle morphogenesis offer promising avenues for improving rice productivity. Here, I reviewed recent studies on the developmental regulatory genes responsible for panicle architecture and explored how these findings can be applied to crop breeding. I also discuss the potential of using wild Oryza genetic resources, highlighting their value not only for scientific exploration but also for breeding innovation. Isolating novel genes related to panicle development and understanding their function are essential for designing diverse panicle architectures by quantitative trait locus pyramiding or genome editing technology. The use of these genetic resources offers a sustainable means to improve rice plant architecture and their resilience to climate change.