1
|
Ratna S, Daniel J. Stress-induced non-replicating Mycobacterium smegmatis incorporates exogenous fatty acids into glycopeptidolipids. Microb Pathog 2023; 174:105943. [PMID: 36502992 DOI: 10.1016/j.micpath.2022.105943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/03/2022] [Accepted: 12/08/2022] [Indexed: 12/13/2022]
Abstract
Nontuberculous mycobacteria (NTM) such as Mycobacterium smegmatis accumulate high levels of glycopeptidolipids (GPLs) on their outer surface. The biosynthesis of GPLs is critically linked to biofilm formation by NTM which also includes opportunistic pathogens such as Mycobacterium abscessus. Although GPLs have been investigated in many earlier studies, the biosynthesis of GPLs using exogenous fatty acids in M. smegmatis subjected to stresses encountered by mycobacteria during infection of the human body has not been studied. Therefore, we subjected M. smegmatis to different combinations of the three stresses of hypoxia, acidic pH and nutrient starvation and report here that the metabolic incorporation of radiolabeled long-chain fatty acids into alkali-stable GPLs was significantly increased under these stress conditions. Endogenously synthesized fatty acids were not preferred for GPL biosynthesis by M. smegmatis subjected to the triple stress combination. Our observations indicate that GPLs may play important roles in cell surface modifications associated with the non-replicating state of M. smegmatis. Our experimental model reported here would be useful in the further study of GPL biosynthesis from exogenous fatty acid sources in M. smegmatis subjected to hypoxia, nutrient starvation and acidic stress conditions and help in the screening of candidate drugs that target this biochemical pathway in pathogenic NTM.
Collapse
Affiliation(s)
- Sushanta Ratna
- Department of Biological Sciences, Purdue University Fort Wayne, Fort Wayne, IN, 46805, USA
| | - Jaiyanth Daniel
- Department of Biological Sciences, Purdue University Fort Wayne, Fort Wayne, IN, 46805, USA.
| |
Collapse
|
2
|
Boonhok R, Sangkanu S, Phumjan S, Jongboonjua R, Sangnopparat N, Kwankaew P, Tedasen A, Lim CL, Pereira MDL, Rahmatullah M, Wilairatana P, Wiart C, Dolma KG, Paul AK, Gupta M, Nissapatorn V. Curcumin effect on Acanthamoeba triangularis encystation under nutrient starvation. PeerJ 2022; 10:e13657. [PMID: 35811814 PMCID: PMC9261923 DOI: 10.7717/peerj.13657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/09/2022] [Indexed: 01/17/2023] Open
Abstract
Background Curcumin is an active compound derived from turmeric, Curcuma longa, and is known for its benefits to human health. The amoebicidal activity of curcumin against Acanthamoeba triangularis was recently discovered. However, a physiological change of intracellular pathways related to A. triangularis encystation mechanism, including autophagy in the surviving amoeba after curcumin treatment, has never been reported. This study aims to investigate the effect of curcumin on the survival of A. triangularis under nutrient starvation and nutrient-rich condition, as well as to evaluate the A. triangularis encystation and a physiological change of Acanthamoeba autophagy at the mRNA level. Methods In this study, A. triangularis amoebas were treated with a sublethal dose of curcumin under nutrient starvation and nutrient-rich condition and the surviving amoebas was investigated. Cysts formation and vacuolization were examined by microscopy and transcriptional expression of autophagy-related genes and other encystation-related genes were evaluated by real-time PCR. Results A. triangularis cysts were formed under nutrient starvation. However, in the presence of the autophagy inhibitor, 3-methyladenine (3-MA), the percentage of cysts was significantly reduced. Interestingly, in the presence of curcumin, most of the parasites remained in the trophozoite stage in both the starvation and nutrient-rich condition. In vacuolization analysis, the percentage of amoebas with enlarged vacuole was increased upon starvation. However, the percentage was significantly declined in the presence of curcumin and 3-MA. Molecular analysis of A. triangularis autophagy-related (ATG) genes showed that the mRNA expression of the ATG genes, ATG3, ATG8b, ATG12, ATG16, under the starvation with curcumin was at a basal level along the treatment. The results were similar to those of the curcumin-treated amoebas under a nutrient-rich condition, except AcATG16 which increased later. On the other hand, mRNA expression of encystation-related genes, cellulose synthase and serine proteinase, remained unchanged during the first 18 h, but significantly increased at 24 h post treatment. Conclusion Curcumin inhibits cyst formation in surviving trophozoites, which may result from its effect on mRNA expression of key Acanthamoeba ATG-related genes. However, further investigation into the mechanism of curcumin in A. triangularis trophozoites arrest and its association with autophagy or other encystation-related pathways is needed to support the future use of curcumin.
Collapse
Affiliation(s)
- Rachasak Boonhok
- Department of Medical Technology, School of Allied Health Sciences, and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Suthinee Sangkanu
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Suganya Phumjan
- Department of Medical Technology, School of Allied Health Sciences, and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Ramita Jongboonjua
- Department of Medical Technology, School of Allied Health Sciences, and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Nawarat Sangnopparat
- Department of Medical Technology, School of Allied Health Sciences, and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Pattamaporn Kwankaew
- Department of Medical Technology, School of Allied Health Sciences, and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Aman Tedasen
- Department of Medical Technology, School of Allied Health Sciences, and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| | - Chooi Ling Lim
- Division of Applied Biomedical Science and Biotechnology, School of Health Sciences, International Medical University, Kuala Lumpur, Malaysia
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials and Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Mohammed Rahmatullah
- Department of Biotechnology and Genetic Engineering, University of Development Alternative, Dhaka, Bangladesh
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Rachathewee, Bangkok, Thailand
| | - Christophe Wiart
- The Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - Karma G. Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences, Sikkim, India
| | - Alok K. Paul
- School of Pharmacy and Pharmacology, University of Tasmania, Hobart, Tasmania, Australia
| | - Madhu Gupta
- Department of Pharmaceutics, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Thai Buri, Nakhon Si Thammarat, Thailand
| |
Collapse
|