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Jin-Fei Lin, Pei-Shan Hu , Yi-Yu Wang , Yue-Tao Tan , Kai Yu, Kun Liao , Qi-Nian Wu, Ting Li, Qi Meng , Jun-Zhong Lin,Ze-Xian Liu , Heng-Ying Pu , Huai-Qiang Ju, Rui-Hua Xu and Miao-Zhen Qiu

 

Phosphorylated NFS1 weakens oxaliplatin-based chemosensitivity of colorectal cancer by preventingPANoptosis

 

DOI: 10.1038/s41392-022-00889-0 PMID: 35221331 PMCID: PMC8882671

 

Abstract：Metabolic enzymes have an indispensable role in metabolic reprogramming, and their aberrant expression or activity has been associated with chemosensitivity. Hence, targeting metabolic enzymes remains an attractive approach for treating tumors. However, the inflfluence and regulation of cysteine desulfurase (NFS1), a rate-limiting enzyme in iron–sulfur (Fe–S) cluster biogenesis, in colorectal cancer (CRC) remain elusive. Here, using an in vivo metabolic enzyme gene-based clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 library screen, we revealed that loss of NFS1 signifificantly enhanced the sensitivity of CRC cells to oxaliplatin. In vitro and in vivo results showed that NFS1 defificiency synergizing with oxaliplatin triggered PANoptosis (apoptosis, necroptosis, pyroptosis, and ferroptosis) by increasing the intracellular levels of reactive oxygen species (ROS). Furthermore, oxaliplatin-based oxidative stress enhanced the phosphorylation level of serine residues of NFS1, which prevented PANoptosis in an S293 phosphorylation-dependent manner during oxaliplatin treatment. In addition, high expression of NFS1, transcriptionally regulated by MYC, was found in tumor tissues and was associated with poor survival and hyposensitivity to chemotherapy in patients with CRC. Overall, the fifindings of this study provided insights into the underlying mechanisms of NFS1 in oxaliplatin sensitivity and identifified NFS1 inhibition as a promising strategy for improving the outcome of platinum-basedchemotherapy in the treatment of CRC.

Weiyan Song, Yi Tong, Yi Li, Jin Tao, Jianghua Li, Jingwen Zhou, Song Liu

 

Expression and characterization of a raw-starch glucoamylase from Aspergillus fumigatus

 

Abstract：The raw-starch glucoamylase (RSGA) digested starch at temperatures lower than the gelatinization point, resulting in lower operational costs. In this study, a RSGA from Aspergillus fumigatus A1163 was characterized after being expressed in Escherichia coli BL21(DE3) and Pichia pastoris (currently known as Komagataella phaffii) GS115, respectively. The extracellular enzyme activity of P. pastoris (pRSGA) was 20 times that of E. coli (eRSGA). The optimal temperatures of pRSGA and eRSGA were 70 ◦C and 60 ◦C, respectively. Furthermore, the half-life of pRSGA at 60 ◦C reached 97 min, which is 78 min longer than that of eRSGA. EndoH reaction and mutation analysis show that glycosylation at N422 is responsible for the differences in catalytic properties between the two recombinant enzymes. pRSGA converted 92.2 % of raw corn starch (200 g/L) into glucose after 36 h at 40 ◦C in the presence of α-amylase and pullulanase. Our findings show that an efficient RSGA and its producing strain can be used to degrade raw starch.

Rong Wang, Piaopiao Wen , Ganglong Yang , Yanyan Feng, Yuanyuan Mi , Xiaoying Wang , Shenglong Zhu and Yong Q. Chen

 

N-glycosylation of GDF15 abolishes its inhibitory effect on EGFR in AR inhibitor-resistant prostate cancer cells

Abstract：Castration-resistance of prostate cancer is one of the most challenging clinical problems. In the present study, we have performed proteomics and glycomics using LNCaP model. Growth differentiation factor-15 (GDF15) level is increased in androgen receptor (AR) inhibitor-resistant cells and the inhibitory effect of GDF15 on epithelial growth factor receptor (EGFR) pathway is relieved by GDF15 N70 glycosylation. Interference of GDF15 (siRNA or N70Q dominant negative) or EGFR pathway (inhibitor or siRNA for EGFR, SRC or ERK) decreases the resistant-cell survival in culture and tumor growth in mice. Our study reveals a novel regulatory mechanism of prostate cancer AR inhibitor resistance, raises the possibility of AR/SRC dual-targeting of castration-resistance of prostate cancer, and lays foundation for the future development of selective inhibitors of GDF15 glycosylation.

Tpullulanase. Our findings show that an efficient RSGA and its

Hongbiao Li, Wenjian Ma, Yunbin Lyv, Song Gao, and Jingwen Zhou
 
 
Abstract：(2S)-Naringenin is an important flflavonoid precursor, with multiple nutritional and pharmacological activities. Both (2S)-naringenin and other flflavonoid production are hindered by poor water solubility and inhibited cell growth. To address this, we increased solubility and

improved cell growth by partially glycosylating (2S)-naringenin to naringenin-7-O-glucoside, which facilitated increased extracellular

secretion, by knocking out endogenous glycosyl hydrolase genes, EXG1 and SPR1, and expressing the glycosyltransferase gene (UGT733C6).

Naringenin-7-O-glucoside synthesis was further improved by optimizing UDP-glucose and shikimate pathways. Then, hydrochloric acid was used

to hydrolyze naringenin-7-O-glucoside to (2S)-naringenin outside the cell. Thus, our optimized Saccharomyces cerevisiae strain E32T19

produced 1184.1 mg/L (2S)-naringenin, a 7.9-fold increase on the starting strain. Therefore. we propose that glycosylation modifification is a useful strategy for the effiffifficient heterologous biosynthesis of (2S)-naringenin in S. cerevisiae.