Skip to Main Content

Yoshinaga, Masafumi

Title: Assistant Professor


Specialty: Environmental microbiology and biochemistry

Department(s): Cellular Biology and Pharmacology

Dr. Yoshinaga has been fascinated by metal(oid) detoxification/homeostasis since he started his research career. Dr. Yoshinaga earned his PhD (Biology, 2007) from Hiroshima University, Japan, where he studied on molecular mechanisms of metal homeostasis/accumulation by marine organisms. After the completion of PhD, he moved to the United States and started his new research career as an environmental microbiologist in Wayne State University. Dr. Yoshinaga joined in FIU HWCOM in 2009 and currently he is working as Assistant Professor in Department of Cellular Biology and Pharmacology. His specific area of interest is to understand the biotransformation of environmental organoarsenicals. Arsenic is the most pervasive environmental toxin, and massive amounts of methylarsenicals such as MSMA (monosodium methylarsenate or MAs(V)) and aromatic arsenicals such as roxarsone have been used as herbicides and growth promoters for animal husbandry, respectively. Those organoarsenicals are degraded into more toxic inorganic forms through microbial activities that impact the environment and contaminate crops and water supplies. However, little is known about the pathways and molecular mechanisms of organoarsenical degradation. His major accomplishments include discovery of a novel organoarsenicals degradation pathway that has two steps, reduction of MAs(V) to the trivalent form [MAs(III)] and demethylation of MAs(III) to trivalent inorganic arsenite [As(III)], catalyzed by different bacterial isolates. Dr. Yoshinaga further identified arsI, the responsible gene for the second step MAs(III) demethylation, characterized biochemical properties of the gene product ArsI and solved its crystal structure. His current major research objective is identification of responsible genes for the first step MAs(V) reduction to elucidate the entire reactions and molecular mechanisms for two-step organoarsenical degradation pathways that he proposes play significant roles in the arsenic biogeochemical cycle. Recently Dr. Yoshinaga has started a new collaborative research on a novel organoarsenical antibiotic and its resistant mechanism.

Selected peer-reviewed publications:

  1. Pawitwar, S. S., Nadar, V. S., Kandegedara, A., Stemmler, T. L., Rosen, B. P., Yoshinaga, M. Biochemical characterization of ArsI: a novel C-As lyase for degradation of environmental organoarsenicals. Environ. Sci. Technol. (2017) in press.
  2. Nadar, V. S., Yoshinaga, M., Pawitwar, S. S., Kandavelu, P., Sankaran,B., Rosen, B. P. Structure of the ArsI C-As lyase: Insights into the mechanism of degradation of organoarsenical herbicides and growth promoters. J. Mol. Biol. 428(11) (2016) 2462-73. PMID: 27107642
  3. Chen, J.*, Yoshinaga, M.*, Garbinski, L. D., Rosen, B. P. Synergistic interaction of glyceraldehydes-3-phosphate dehydrogenase and ArsJ, a novel organoarsenical efflux permease, confers arsenate resistance. Mol. Microbiol. 100(6). (2016). 945-53. PMID: 26991003 (*Contributed equally to this work)
  4. Yoshinaga, M., Rosen, B. P. A C·As lyase for degradation of environmental organoarsenical herbicides and animal husbandry growth promoters. Proc. Natl. Acad. Sci. U. S. A. 111(21). (2014). 7701-6. PMID: 24821808
  5. Zhu, Y. G., Yoshinaga, M., Zhao, F. J., Rosen, B. P. Earth abides arsenic biotransformations. Annu. Rev. Earth Planet. Sci. 42. (2014) 443-67. PMID: 26778863
  6. Yoshinaga, M., Cai, Y., Rosen, B. P. Demethylation of methylarsonic acid by a microbial community. Environ. Microbiol. 13(5). (2011). 1205-1215. PMID: 21272184
  7. Carbrey, J. M., Song, L., Zhou, Y., Yoshinaga, M., Rojek, A., Wang, Y., Liu, Y., Lujan, H. L., DiCarlo, S. E., Nielsen, S., Rosen, B. P., Agre, P., Mukhopadhyay, R. Reduced arsenic clearance and increased toxicity in aquaglyceroporin-9-null mice. Proc. Natl. Acad. Sci. U. S. A. 106(37). (2009). 15956-60. PMID: 19805235

Curriculum Vitae:

  • Ph.D., Biology (2003-2007): Hiroshima University Graduate School of Science
  • Postdoctoral Fellow: Environmental Microbiology and Biochemistry (2007-2009): Wayne State University School of Medicine
  • Postdoctoral Research Associate: Environmental Microbiology and Biochemistry (2009-2012): Florida International University Herbert Wertheim College of Medicine
  • Assistant Professor: Environmental Microbiology and Biochemistry (2012-2015): Florida International University Herbert Wertheim College of Medicine
  • Assistant Professor: Occupational and Environmental Health (2015-2016): Nagoya University Graduate School of Medicine