Newly synthesized mRNA escapes translational repression during the acute phase of the mammalian unfolded protein response

Detection of biofilm formation and antibiotics resistance of Staphylococcus spp. isolated from humans' and birds' oral cavities

Background

Staphylococcus spp. are widely distributed in nature and can cause nosocomial, skin infections, and foodborne illness, and it may lead to severe financial losses in birds by causing systemic infection in numerous organs.

Aim

This study was conducted to determine the prevalence of Staphylococcus spp. in humans and birds in Baghdad city.

Methods

Seventy-six oral cavity swabs were collected, including 41 from birds and 35 from breeders. All samples were examined by bacteriological methods and identified by using the VITEK technique, the samples were then further studied to test the ability of biofilm formation, and multidrug-resistant (MDR) factors and MAR index were tested with the use of seven antibiotics.

Results

Among the 76 oral swabs, 37 samples were positive (48.68%) for Staphylococcus spp.: 7 human samples (20%) and 30 bird samples (73.17%). In humans, Staphylococcus lentus was the most prevalent (42.85%) followed by Staphylococcus aureus (28.57%), Staphylococcus hominis and Staphylococcus sciuri were at (14.29%) to each. In birds, Staphylococcus pseudintermedius, Staphylococcus gallinarum, S. lentus, Staphylococcus haemolyticus, Staphylococcus spp, S. sciuri, and Staphylococcus xylosus were detected in 36.67%, 16.67%, 10%, 10%, 13.33%, 3.33% and 3.33%, respectively. Staphylococcus isolates from the human samples demonstrated that only S. lentus was resistant 33.33% to ME, OX, and SXT. Furthermore, one of them was MDR and high MAR index value. The antimicrobial pattern of Staphylococcus spp. isolated from birds was as follows S. pseudintermedius isolates demonstrated 100% resistance to CN, CIP, SXT, and MDR (100%) and high MAR indices value; S. xylosus was resistant 100% against ME, CN, SXT, and Do and it was MDR with high MAR index; S. lentus was resistant 25% against ME, OX, C, and SXT, whereas, S. gallinarum was resistant 33.33% against ME and OX. The results demonstrated that biofilm formation of the Staphylococcus spp. isolated from human samples were weak biofilm formers: S. lentus, S. hominis, and S. aureus, while other S. aureus (50%) was moderate. In birds, the majority of the isolates had non-biofilm-producing capabilities, while 80% of S. lentus and 100% of S. xylosus showed moderate biofilm formation.

Conclusion

Healthcare problem was observed in this study due to high MDR and MAR index among Staphylococcus spp. isolated from pet birds to their owners and vice versa.

Turnover of PPP1R15A mRNA encoding GADD34 controls responsiveness and adaptation to cellular stress

The integrated stress response (ISR) is a key cellular signaling pathway activated by environmental alterations that represses protein synthesis to restore homeostasis. To prevent sustained damage, the ISR is counteracted by the upregulation of growth arrest and DNA damage-inducible 34 (GADD34), a stress-induced regulatory subunit of protein phosphatase 1 that mediates translation reactivation and stress recovery. Here, we uncover a novel ISR regulatory mechanism that post-transcriptionally controls the stability of PPP1R15A mRNA encoding GADD34. We establish that the 3' untranslated region of PPP1R15A mRNA contains an active AU-rich element (ARE) recognized by proteins of the ZFP36 family, promoting its rapid decay under normal conditions and stabilization for efficient expression of GADD34 in response to stress. We identify the tight temporal control of PPP1R15A mRNA turnover as a component of the transient ISR memory, which sets the threshold for cellular responsiveness and mediates adaptation to repeated stress conditions.