Decreased biofilm formation ability of Acinetobacter baumannii after spaceflight on China's Shenzhou 11 spacecraft

Abstract

China has prepared for construction of a space station by the early 2020s. The mission will require astronauts to stay on the space station for at least 180 days. Microbes isolated from the International Space Station (ISS) have shown profound resistance to clinical antibiotics and environmental stresses. Previous studies have demonstrated that the space environment could affect microbial survival, growth, virulence, biofilms, metabolism, as well as their antibiotic‐resistant phenotypes. Furthermore, several studies have reported that astronauts experience a decline in their immunity during long‐duration spaceflights. Monitoring microbiomes in the ISS or the spacecraft will be beneficial for the prevention of infection among the astronauts during spaceflight. The development of a manned space program worldwide not only provides an opportunity to investigate the impact of this extreme environment on opportunistic pathogenic microbes, but also offers a unique platform to detect mutations in pathogenic bacteria. Various microorganisms have been carried on a spacecraft for academic purposes. Acinetobacter baumannii is a common multidrug‐resistant bacterium often prevalent in hospitals. Variations in the ability to cope with environmental hazards increase the chances of microbial survival. Our study aimed to compare phenotypic variations and analyze genomic and transcriptomic variations in A. baumannii among three different groups: SS1 (33 days on the Shenzhou 11 spacecraft), GS1 (ground control), and Aba (reference strain). Consequently, the biofilm formation ability of the SS1 strain decreased after 33 days of spaceflight. Furthermore, high‐throughput sequencing revealed that some differentially expressed genes were downregulated in the SS1 strain compared with those in the GS1 strain. In conclusion, this present study provides insights into the environmental adaptation of A. baumannii and might be useful for understanding changes in the opportunistic pathogenic microbes on our spacecraft and on China's future ISS.

Effects of Simulated Microgravity on the Physiology of Stenotrophomonas maltophilia and Multiomic Analysis

“…These results were consistent with our results. However, Zhao et al (2019) found that Acinetobacter baumannii showed decreased biofilm formation after a spaceflight on the Shenzhou 11 spacecraft of China. Klebsiella pneumoniae formed different subgroups, M1 and M2, on solid medium, and an increased biofilm forming ability was found in M1 compared with that in M2 in SMG (Wang et al, 2017).…”

“…Drug susceptibility testing (DST) was performed using the disk diffusion method based on the CLSI M100 Ed30 document (CLSI, 2020): trimethoprim-sulfamethoxazole (SXT, 25 μg), levofloxacin (LEV, 5 μg), and minocycline (MNO, 30 μg). The entire surface of the Petri dish containing Mueller-Hinton agar (MHA) was covered with a specific inoculum (10 7 -10 8 CFU/ ml; Zhao et al, 2019), and then, the plate was dried for 15 min. The diameter of the zone of inhibition was measured after incubation for 18 h at 37°C.…”

“…The SMS and SMN samples, which were cultivated for 14 days in the previous step of the qualitative measurement, were collected and diluted to 10 7 CFU/ml. The SMO sample was also diluted to 10 7 CFU/ml (Zhao et al, 2019). The three samples were diluted with LB medium at a volume ratio of 1:100, and added to a 24-well plate.…”

Decreased biofilm formation in Proteus mirabilis after short-term exposure to a simulated microgravity environment

“…As a result, it showed that Pseudomonas aeruginosa showed increased biofilm formation and new structure formation during space flight (Kim et al, 2013). In addition, studies have shown that space flight reduces the biofilm forming ability of multidrug-resistant Acinetobacter baumannii (Zhao et al, 2019). Studies have shown that the uncertainty in the treatment of P. mirabilis is closely related to the intensity of biofilm formation (Deva et al, 2013).…”

Quorum Sensing Inhibition or Quenching in Acinetobacter baumannii: The Novel Therapeutic Strategies for New Drug Development

“…Acinetobacter baumannii , a non-fermenter Gram-negative opportunistic pathogen, associated with nosocomial infection, such as pneumonia, bloodstream, and urinary tract infections ( Karageorgopoulos and Falagas, 2008 ; Harding et al, 2018 ). Acinetobacter baumannii infections often occur in patients with prolonged hospitalization and with long-term exposition to antimicrobials, so that its multi-drug resistance to most of the clinic antibiotics ( Garnacho-Montero and Timsit, 2019 ; Zhao et al, 2019 ). In recent decades, the emergence of multi- and even pan-drug resistant A. baumannii has brought a tremendous challenge to the infection control and treatment plans in clinical treatment ( Dijkshoorn et al, 2007 ; Karageorgopoulos and Falagas, 2008 ).…”