acetyl-CoA carboxylase evolves fused biotin carboxylase and biotin carboxyl carrier protein to complete carboxylation activity.

Acetyl-CoA carboxylases (ACCs) convert acetyl-CoA to malonyl-CoA, a key step in fatty acid biosynthesis and autotrophic carbon fixation pathways. Three functionally distinct components, biotin carboxylase (BC), biotin carboxyl carrier protein (BCCP), and carboxyltransferase (CT), are either separated or partially fused in different combinations, forming heteromeric ACCs. However, an ACC with fused BC-BCCP and separate CT has not been identified, leaving its catalytic mechanism unclear.

Multi-scale failure mechanisms of hydraulic engineering exposed to seasonally frozen salinization environment: Integrating SBAS-InSAR and mechanical experiments.

Constructing hydraulic engineering ensures agricultural development and improves salinization environments. However, in seasonally frozen salinization regions, hydraulic engineering is prone to deformation failure. Leakage from canal raises the regional groundwater level, triggering secondary salinization environmental issues.

Analysis of Risk Factors of Pelvic Organ Prolapse in Postmenopausal Women and Construction of Prediction Model.

Background: The incidence of Pelvic organ prolapse (POP) was as high as 50% in women, with the main symptoms of vaginal tissue prolapse, accompanied by urination, defecation, and sexual dysfunction, which affected patients' quality of life. POP is more prominent in postmenopausal women due to various factors. By constructing a model, we predict POP and expect to reduce the incidence of POP.

Lateral lymph node metastasis in papillary thyroid microcarcinoma: a study of 5241 follow-up patients.

Purpose: To investigate the impact of lateral lymph node metastasis in papillary thyroid microcarcinoma (PTMC).

Methods: 5241 PTMC patients with follow-up information were enrolled in the current study. These patients underwent primary surgery in our situation from January 1997 to December 2016.

Tolrestat acts atypically as a competitive inhibitor of the thermostable aldo-keto reductase Tm1743 from Thermotoga maritima.

Tolrestat and epalrestat have been characterized as noncompetitive inhibitors of aldo-ketone reductase 1B1 (AKR1B1), a leading drug target for the treatment of type 2 diabetes complications. However, clinical applications are limited for most AKR1B1 inhibitors due to adverse effects of cross-inhibition with other AKRs. Here, we report an atypical competitive binding and inhibitory effect of tolrestat on the thermostable AKR Tm1743 from Thermotoga maritima.

The C-terminal domain conformational switch revealed by the crystal structure of malyl-CoA lyase from Roseiflexus castenholzii.

Malyl-coenzyme A lyase (MCL) is a carbon-carbon bond lyase that catalyzes the reversible cleavage of coenzyme A (CoA) thioesters in multiple carbon metabolic pathways. This enzyme contains a CitE-like TIM barrel and an additional C-terminal domain that undergoes conformational changes upon substrate binding. However, the structural basis underlying these conformational changes is elusive.

Substrate Specificity of Acyltransferase Domains for Efficient Transfer of Acyl Groups.

Acyltransferase domains (ATs) of polyketide synthases (PKSs) are critical for loading of acyl groups on acyl carrier protein domains (A) via - and -acylation reactions, to produce structurally diverse polyketides. However, the interaction specificity between ATs and unusual acyl units is rarely documented. In YN06, we found that AT4 [an AT in the fourth module of tacrolimus (FK506) PKS] transferred both allylmalonyl (allmal) and emthylmalonyl (ethmal) units to ACPs, which was supposed responsible for the production of both FK506 and its analog FK520, respectively.

An acyltransferase domain of FK506 polyketide synthase recognizing both an acyl carrier protein and coenzyme A as acyl donors to transfer allylmalonyl and ethylmalonyl units.

Unlabelled: Acyltransferase (AT) domains of polyketide synthases (PKSs) usually use coenzyme A (CoA) as an acyl donor to transfer common acyl units to acyl carrier protein (ACP) domains, initiating incorporation of acyl units into polyketides. Two clinical immunosuppressive agents, FK506 and FK520, are biosynthesized by the same PKSs in several Streptomyces strains. In this study, characterization of AT4FkbB (the AT domain of the fourth module of FK506 PKS) in transacylation reactions showed that AT4FkbB recognizes both an ACP domain (ACPT csA) and CoA as acyl donors for transfer of a unique allylmalonyl (AM) unit to an acyl acceptor ACP domain (ACP4FkbB), resulting in FK506 production.

Hydrogen sulfide improves drought tolerance in Arabidopsis thaliana by microRNA expressions.

Hydrogen sulfide (H2S) is a gasotransmitter and plays an important role in many physiological processes in mammals. Studies of its functions in plants are attracting ever growing interest, for example, its ability to enhance drought resistance in Arabidopsis. A general role of microRNAs (miRNAs) in plant adaptive responses to drought stress has thereby increased our interest to delve into the possible interplay between H2S and miRNAs.

Hydrogen sulfide improves drought resistance in Arabidopsis thaliana.

Hydrogen sulfide (H(2)S) plays a crucial role in human and animal physiology. Its ubiquity and versatile properties have recently caught the attention of plant physiologists and biochemists. Two cysteine desulfhydrases (CDes), L-cysteine desulfhydrase and D-cysteine desulfhydrase, were identified as being mainly responsible for the degradation of cysteine in order to generate H(2)S.