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Plant GDP-D-mannose pyrophosphorylase (GMPase) catalyzes a committed step in ascorbic acid biosynthesis pathway.

In this work, the branching ratio $\mathcal{B}[B\ensuremath{\rightarrow}K{\ensuremath{\chi}}_{c0}(2P)]$ is extracted for the first time through the fit fractions in the newly measured $B\ensuremath{\rightarrow}KD\overline{D}$ process by LHCb. With the rescattering mechanism, this extracted branching ratio is reproduced well. Our study further enforces the role of the newly measured $B\ensuremath{\rightarrow}KD\overline{D}$ process to establish the ${\ensuremath{\chi}}_{c0}(2P)$ charmonium state, which is a crucial step when constructing the charmonium family.

In this work, we propose the $4S\text{\ensuremath{-}}3D$ mixing scheme to assign the $\mathrm{\ensuremath{\Upsilon}}(10753)$ into the conventional bottomonium family. Under this interpretation, we further study its hidden-bottom hadronic decays with a ${\ensuremath{\eta}}^{(\ensuremath{'})}$ or $\ensuremath{\omega}$ emission, which include $\mathrm{\ensuremath{\Upsilon}}(10753)\ensuremath{\rightarrow}\mathrm{\ensuremath{\Upsilon}}(1S){\ensuremath{\eta}}^{(\ensuremath{'})}$, $\mathrm{\ensuremath{\Upsilon}}(10753)\ensuremath{\rightarrow}{h}_{b}(1P)\ensuremath{\eta}$, and $\mathrm{\ensuremath{\Upsilon}}(10753)\ensuremath{\rightarrow}{\ensuremath{\chi}}_{bJ}\ensuremath{\omega}$ ($J=0$, 1, 2) processes. Since the $\mathrm{\ensuremath{\Upsilon}}(10753)$ is above the $B\overline{B}$ threshold, the coupled-channel effect cannot be ignored; thus, when calculating partial decay widths of these $\mathrm{\ensuremath{\Upsilon}}(10753)$ hidden-bottom decays, we apply the hadronic loop mechanism. Our result shows that these discussed decay processes own considerable branching fractions with an order of magnitude of ${10}^{\ensuremath{-}4}--{10}^{\ensuremath{-}3}$, which can be accessible at Belle II and other future experiments.

The semileptonic decays of ${\mathrm{\ensuremath{\Lambda}}}_{b}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Lambda}}}_{c}^{(*)}\ensuremath{\ell}{\ensuremath{\nu}}_{\ensuremath{\ell}}$ and ${\mathrm{\ensuremath{\Lambda}}}_{c}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Lambda}}}^{(*)}\ensuremath{\ell}{\ensuremath{\nu}}_{\ensuremath{\ell}}$ are studied in the light-front quark model in this work. Instead of the quark-diquark approximation, we use the three-body wave functions obtained by baryon spectroscopy. The ground states $(1/{2}^{+})$, the $\ensuremath{\lambda}$-mode orbital excited states $(1/{2}^{\ensuremath{-}})$, and the first radial excited states $(1/{2}^{+})$ of ${\mathrm{\ensuremath{\Lambda}}}_{(c)}^{(*)}$ are considered. The discussions are given for the form factors, partial widths, branching fractions, leptonic forward-backward asymmetries, hadron polarizations, lepton polarizations, and the lepton flavor universalities. Our results are useful for the inputs of heavy baryon decays and understanding the baryon structures, and helpful for experimental measurements.

The reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide) is the penultimate step of chlorophyll biosynthesis. In oxygenic photosynthetic bacteria, algae, and plants, this reaction can be catalyzed by the light-dependent Pchlide oxidoreductase (LPOR), a member of the short-chain dehydrogenase superfamily sharing a conserved Rossmann fold for NAD(P)H binding and the catalytic activity. Whereas modeling and simulation approaches have been used to study the catalytic mechanism of this light-driven reaction, key details of the LPOR structure remain unclear. We determined the crystal structures of LPOR from two cyanobacteria, Synechocystis sp. PCC 6803 and Thermosynechococcus elongatus . Structural analysis defines the LPOR core fold, outlines the LPOR–NADPH interaction network, identifies the residues forming the substrate cavity and the proton-relay path, and reveals the role of the LPOR-specific loop. These findings provide a basis for understanding the structure-function relationships of the light-driven Pchlide reduction.

Objective To evaluate the frequency of azoospermia factor (AZFa) microdeletions among infertile men and establish a new high-throughput sequencing method to detect novel deletion types. Materials and Methods A total of 3731 infertile men were included. Karyotype analysis was performed using G-band staining of peripheral blood lymphocytes. Polymerase chain reaction (PCR) amplification using specific sequence-tagged sites (STS) was performed to screen for AZF region microdeletions of the Y chromosome. A novel semiconductor sequencing method was established to detect high-resolution AZFa microdeletions. Results Of 3731 infertile men, 341 (9.14%) had microdeletions in AZFa, AZFb, or AZFc. Thirteen of these (3.81%) had a deletion in the AZFa region (mean age: 27.3 ± 4 years, range: 22-34), which included 12 subjects with a normal karyotype (46, XY) and 1 with Klinefelter syndrome (47, XXY). Four of 10 subjects with complete AZFa microdeletions (sY86 and sY84 loss) underwent semiconductor sequencing. They all had DNA sequence deletions from nt 14469266 to 15195932, whereas their fathers had no deletions. One subject with partial AZFa microdeletion (sY86 loss) and his father underwent semiconductor sequencing and STS-PCR analysis. The same deletion (sY86 loss with DNA sequence deletion from nt 14469266 to 14607672) was identified in both subjects. Forty sperm donators and 50 infertile men showed no AZFa microdeletions by either method. Conclusion AZFa deletions are present at a low frequency in men with azoospermia or oligozoospermia. Novel sequencing methods can be used for these patients to reveal high-resolution AZFa microdeletions.