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991.
Yachang Cheng Wolfgang Fiedler Martin Wikelski Andrea Flack 《Ecology and evolution》2019,9(16):8945-8952
Human‐induced changes in the climate and environment that occur at an unprecedented speed are challenging the existence of migratory species. Faced with these new challenges, species with diverse and flexible migratory behaviors may suffer less from population decline, as they may be better at responding to these changes by altering their migratory behavior. At the individual level, variations in migratory behavior may lead to differences in fitness and subsequently influence the population's demographic dynamics. Using lifetime GPS bio‐logging data from 169 white storks (Ciconia ciconia), we explore whether the recently shortened migration distance of storks affects their survival during different stages of their juvenile life. We also explore how other variations in migratory decisions (i.e., time, destination), movement activity (measured using overall body dynamic acceleration), and early life conditions influence juvenile survival. We observed that their first autumn migration was the riskiest period for juvenile white storks. Individuals that migrated shorter distances and fledged earlier experienced lower mortality risks. In addition, higher movement activity and overwintering “closer‐to‐home” (with 84.21% of the tracked individuals stayed Europe or North Africa) were associated with higher survival. Our study shows how avian migrants can change life history decisions over only a few decades, and thus it helps us to understand and predict how migrants respond to the rapidly changing world. 相似文献
992.
993.
Yang Siyuan Xu Weizhi Liu Cheng Jin Jiaqi Li Xueying Jiang Yuhan Zhang Lei Meng Xianbin Zhan Jun Zhang Hongquan 《中国科学:生命科学英文版》2022,65(1):129-141
Science China Life Sciences - Large tumor suppressor 1 (LATS1) is the key kinase controlling activation of Hippo signalling pathway. Post-translational modifications of LATS1 modulate its kinase... 相似文献
994.
995.
Xiao‐Yan Liu Steven R. Manchester rew C. Rozefelds Cheng Quan Jian‐Hua Jin 《植物分类学报:英文版》2022,60(2):456-471
The genus Elaeocarpus contains approximately 360 species and occurs in mesic forest communities from India, through to China, Southeast Asia, New Guinea, Australia, and New Caledonia. Elaeocarpus fossils are best known from the Eocene to the Miocene of Australia and the late Pliocene–early Pleistocene of India, but have not been documented from East Asia before. Here we describe six new species of Elaeocarpus, E. nanningensis sp. nov. from the late Oligocene Yongning Formation of the Nanning Basin, E. presikkimensis sp. nov. from the Miocene Erzitang Formation of the Guiping Basin, E. prerugosus sp. nov., E. prelacunosus sp. nov., E. preserratus sp. nov., and E. preprunifolioides sp. nov. from the late Miocene Foluo Formation of the Nankang Basin in Guangxi, South China. This is the first reliable report for the genus occurring in East Asia, and the fossils indicate that Elaeocarpus had colonized this region by the late Oligocene and represented by a morphologically diverse group of species by the late Miocene. This sheds new insights into the timing and migration patterns of the genus in East Asia. Elaeocarpus is typically a rainforest genus occurring in mesic forests. Based on the habitat of their morphologically similar modern relatives we propose that these three sedimentary basins were warm and wet adjacent to mountainous regions with the evergreen or rain forests during the late Oligocene to Miocene. 相似文献
996.
997.
Ya-Yun Cheng Tae Hyeon Park Hyunbin Seong Tae-Jip Kim Nam Soo Han 《Microbial biotechnology》2022,15(11):2717-2729
PLA (3-D-phenyllactic acid) is an ideal antimicrobial and immune regulatory compound present in honey and fermented foods. Sporolactobacillus inulinus is regarded as a potent D-PLA producer that reduces phenylpyruvate (PPA) with D-lactate dehydrogenases. In this study, PLA was produced by whole-cell bioconversion of S. inulinus ATCC 15538. Three genes encoding D-lactate dehydrogenase (d-ldh1, d-ldh2, and d-ldh3) were cloned and expressed in Escherichia coli BL21 (DE3), and their biochemical and structural properties were characterized. Consequently, a high concentration of pure D-PLA (47 mM) was produced with a high conversion yield of 88%. Among the three enzymes, D-LDH1 was responsible for the efficient conversion of PPA to PLA with kinetic parameters of Km (0.36 mM), kcat (481.10 s−1), and kcat/Km (1336.39 mM−1 s−1). In silico structural analysis and site-directed mutagenesis revealed that the Ile307 in D-LDH1 is a key residue for excellent PPA reduction with low steric hindrance at the substrate entrance. This study highlights that S. inulinus ATCC 15538 is an excellent PLA producer, equipped with a highly specific and efficient D-LDH1 enzyme. 相似文献
998.
Youli Yu Huiyuan Cheng Shu Wang Mei Wei Congyan Wang Daolin Du 《Journal of Plant Ecology》2022,15(3):494
干旱利于刺苋的竞争优势
干旱可以影响入侵植物的生长和土壤酶活性。因此,非常有必要评估干旱背景下入侵植物的竞争优势以及入侵植物和干旱对土壤酶活性的影响。本研究旨在分析干旱背景下起源于热带美洲的入侵植物刺苋(Amaranthus spinosus)与本地植物苋菜(Amaranthus tricolor)共存时的竞争优势和土壤酶活性。通过栽植实验进行刺苋与苋菜的竞争共栽培,并进行不同水平的干旱处理,即:(i)对照;(ii)轻度干旱;(iii)重度干旱。实验结束后测定两种苋属植物的功能性状、渗透调节、抗氧化酶活性以及土壤pH、电导率、土壤微生物生物量碳含量和土壤酶活性。干旱背景下,刺苋的相对竞争强度和相对优势度均高于苋菜。因此,干旱利于刺苋的竞争优势。干旱背景下,刺苋的土壤水溶性盐含量和蔗糖水解能力均大于苋菜。而较高的土壤水溶性盐含量和蔗糖水解能力利于刺苋对养分的获取和利用。 相似文献
999.
Alkaliphiles are considered more suitable chassis than traditional neutrophiles due to their excellent resistance to microbial contamination. Alkaliphilic Bacillus sp. N16-5, an industrially interesting strain with great potential for the production of lactic acid and alkaline polysaccharide hydrolases, can only be engineered genetically by the laborious and time-consuming homologous recombination. In this study, we reported the successful development of a CRISPR/Cas9-based genome editing system with high efficiency for single-gene deletion, large gene fragment deletion and exogenous DNA chromosomal insertion. Moreover, based on a catalytically dead variant of Cas9 (dCas9), we also developed a CRISPRi system to efficiently regulate gene expression. Finally, this efficient genome editing system was successfully applied to engineer the xylose metabolic pathway for the efficient bioproduction of D -lactic acid. Compared with the wild-type Bacillus sp. N16-5, the final engineered strain with XylR deletion and AraE overexpression achieved 34.3% and 27.7% increases in xylose consumption and D -lactic acid production respectively. To our knowledge, this is the first report on the development and application of CRISPR/Cas9-based genome editing system in alkaliphilic Bacillus, and this study will significantly facilitate functional genomic studies and genome manipulation in alkaliphilic Bacillus, laying a foundation for the development of more robust microbial chassis. 相似文献
1000.