1Eye Hospital, Wenzhou Medical University, School of Ophthalmology and Optometry, Biomedical Engineering, Wenzhou 325027, China; 2School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China
Abstract:Objective: To study the effects of Fe3+ and hemoglobin (Hb) iron on the ability of Bacillus cereus to grow when isolated from the eye. Methods: In this experimental study, 26 patients with post-traumatic Bacillus cereus endophthalmitis were recruited from Eye Hospital, Wenzhou Medical University and 26 strains of Bacillus cereus isolated from the eyes were obtained. The strains were divided into a light-perception (LP) group and no-light-perception (NLP) group, based on whether the patient's light perception was preserved after treatment, and the Bacillus cereus strain ATCC14579 was used as a control group. Optical density (OD) values of different strains of growth in an iron-deficient environment, different Fe3+ concentration environments, and Hb environments were measured. Data analysis was performed by independent samples t-tests. Results: The OD values of 26 strains of Bacillus cereus isolated from the eye and grown in an iron-deficient environment were weaker than the Bacillus cereus standard strain ATCC14579 (t=54.098, P<0.001). By increasing the Fe3+concentrations within a certain range (0-500 μmol/L), the OD values of the strains were gradually enhanced, and when the Fe3+ concentration was higher than 1 000 μmol/L, the OD values of the bacteria decreased. Moreover, in the environment where Fe3+ or Hb was the main iron resource, the OD values of the strains of the growth in the NLP group were stronger than that of the LP group (t=2.618, P=0.015; t=2.202, P=0.037). Conclusions: The growth of Bacillus cereus isolated from the eyes are more dependent on Fe3+, and the clinical prognosis is worse after infection with bacteria that grows faster in Fe3+ or Hb iron environments.
李彧钰, 朱葛菁, 徐芳依, 杨媛媛, 徐一, 毛丽萍, 郑美琴. Fe3+及血红蛋白铁对眼源性蜡样芽胞杆菌生长能力的影响[J]. 中华眼视光学与视觉科学杂志, 2019, 21(2): 86-91.
Yuyu Li, Gejing Zhu, Fangyi Xu, Yuanyuan Yang, Yi Xu, Liping Mao, Meiqin Zheng. Effects of Fe3+ and Hemoglobin Iron on the Growth Ability of Bacillus Cereus Isolated from the Eye. Chinese Journal of Optometry Ophthalmology and Visual science, 2019, 21(2): 86-91. DOI: 10.3760/cma.j.issn.1674-845X.2019.02.002
Andrews S, Norton I, Salunkhe AS, et al.Control of iron metabolism in bacteria. Met Ions Life Sci, 2013, 12: 203-239. DOI:10.1007/978-94-007-5561-1_7.
[3]
Hayrapetyan H, Siezen R, Abee T, et al.Comparative genomics of iron-transporting systems in Bacillus cereus strains and impact of iron sources on growth and biofilm formation. Front Microbiol, 2016, 7: 842. DOI:10.3389/fmicb.2016.00842.
[4]
Daou N, Buisson C, Gohar M, et al.IlsA, a unique surface protein of Bacillus cereus required for iron acquisition from heme, hemoglobin and ferritin. PLoS Pathog, 2009, 5(11): e1000675. DOI: 10.1371/journal.ppat.1000675.
[5]
Oexle H, Gnaiger E, Weiss G.Iron-dependent changes in cellular energy metabolism: influence on citric acid cycle and oxidative phosphorylation. Biochim Biophys Acta, 1999, 1413(3): 99-107.
[6]
Volani C, Doerrier C, Demetz E, et al.Dietary iron loading negatively affects liver mitochondrial function. Metallomics, 2017, 9(11): 1634-1644. DOI:10.1039/c7mt00177k.
[7]
Muckenthaler MU, Rivella S, Hentze MW, et al.A red carpet for iron metabolism. Cell, 2017, 168(3): 344-361. DOI:10.1016/j.cell.2016.12.034.
[8]
Porcheron GDozois CM.Interplay between iron homeostasis and virulence: Fur and RyhB as major regulators of bacterial pathogenicity. Vet Microbiol, 2015, 179(1-2): 2-14. DOI: 10.1016/j.vetmic.2015.03.024.
[9]
Sineva E, Shadrin A, Rodikova EA, et al.Iron regulates expression of Bacillus cereus hemolysin II via global regulator Fur. J Bacteriol, 2012, 194(13): 3327-3335.DOI:10.1128/JB.00199-12.
[10]
Kim IH, Wen Y, Son JS, et al.The fur-iron complex modulates expression of the quorum-sensing master regulator, SmcR, to control expression of virulence factors in Vibrio vulnificus. Infect Immun, 2013, 81(8): 2888-2898. DOI: 10.1128/iai.00375-13.
[11]
Sheldon JR, Laakso HA, Heinrichs DE.Iron acquisition strategies of bacterial pathogens. Microbiol Spectr, 2016, 4(2). DOI: 10.1128/microbiolspec.VMBF-0010-2015.
[12]
Carver PL.Metal ions and infectious diseases. An overview from the clinic. Met Ions Life Sci, 2013, 13:1-28.DOI:10.1007/978-94-007-7500-8_1.
[13]
Braun VHantke K.Recent insights into iron import by bacteria. Curr Opin Chem Biol, 2011, 15(2): 328-334. 10.1016/j.cbpa.2011.01.005.
[14]
Choby JE, Skaar EP.Heme synthesis and acquisition in bacterial pathogens. J Mol Biol, 2016, 428(17): 3408-3428.DOI:10.1016/j.jmb.2016.03.018.