Chem 32002 ± Fall 2020: Biochemistry article review
1. General information
Student name & email:
Article reference (including Author names / Title of article / Source (journal / newspaper / site) / Year /
Volume / Page numbers):
Mitra, A., Ko, Y., Cingolani, G. et al. Heme and hemoglobin utilization by Mycobacterium
tuberculosis. Nat Commun 10, 4260 (2019).
Citation DOI: https://doi.org/10.1038/s41467-019-12109-5
2. Summary of article (1500-2000 words):
Mycobacterium tuberculosis (Mtb) is a type of bacteria that is part of the respiratory system which has
a waxy layer because of the mycolic acid present. Majority of the iron that our body stores is found in
heme, which is hydrophobic. Heme has the highest iron source, and it is estimated to have about
70% of the total iron in our body. Iron helps perform a critical function when it comes to taking care of
bacterial infections. There is evidence that shows the high amount of iron can cause a high risk of
Tuberculosis (TB) pathogenesis. Due to gene variation such as haptoglobin, high levels of iron build
up in the blood cell which could lead to an increased risk of TB.
In the event of severe low levels of iron, Mtb secretes siderophores, which are molecules that have
the ability for high iron-binding affinity. It is secreted by bacteria and is used for iron transport through
the cell membrane. It was first proposed that MmpL3 and MmpL11 were responsible for heme
utilization, but it was later found out that they were used as a pump to export lipids as a maintenance
function for the mycobacterial cell wall. It is still unclear whether MmpL3 and MmpL11 do play a role
in the heme utilization by Mtb. It was later discovered that heme-binding proteins present on the cell
surface such as PPE36 and PPE62 were used for heme utilization by Mtb. The study also wanted to
test where PPE36 and PPE62 were responsible for hemoglobin utilization as well. They were placed
in a medium with heme and hemoglobin. Because there was no growth of Δppe36 mutant with heme
or hemoglobin as their only iron source, this tells us that PPE36 is required for both heme and
hemoglobin utilization. Similar results were found for PPE62. When the siderophores deficient mutant
was infected, the survival rate decreased drastically after 72 hours. Based on their study, it showed
that PPE36 was essential for heme utilization and nothing was mentioned about PPE37. But recently
we see that PPE37 is essential and PPE36 is not. The reason for this could be that gene variation
caused changes in the requirements for the Mtb utilization. It was important to note that the study did
not test whether PPE37 played any role in heme and hemoglobin utilization by Mtb.
The study tested whether Dpp transporter plays a part in heme utilization. First, by doing a
homologous recombination, the dpp operon was removed from the Mtb strain. Homologous
Citation: Tsang, N.Y.; Li, W.-F.;
Varhegyi, E.; Rong, L.; Zhang, H.-J.
Ebola Entry Inhibitors Discovered
from Maesa perlarius. Int. J. Mol. Sci.
2022, 23, 2620. https://doi.org/
Received: 31 December 2021
Accepted: 23 February 2022
Published: 27 February 2022
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
Copyright: © 2022 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
International Journal of
Ebola Entry Inhibitors Discovered from Maesa perlarius
Nga Yi Tsang 1,† , Wan-Fei Li 1,†, Elizabeth Varhegyi 2,† , Lijun Rong 2,* and Hong-Jie Zhang 1,*
1 Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon,
Hong Kong, China; [email protected] (N.Y.T.); [email protected] (W.-F.L.)
2 Department of Microbiology and Immunology, College of Medicine, University of Illinois Chicago,
909 South Wolcott Ave, Chicago, IL 60612, USA; [email protected]
* Correspondence: [email protected] (L.R.); [email protected] (H.-J.Z.); Tel.: +1-312-3550203 (L.R.);
† These authors contributed equally to this work.
Abstract: Ebola virus disease (EVD), a disease caused by infection with Ebola virus (EBOV), is
characterized by hemorrhagic fever and a high case fatality rate. With limited options for the
treatment of EVD, anti-Ebola viral therapeutics need to be urgently developed. In this study, over
500 extracts of medicinal plants collected in the Lingnan region were tested against infection with
Ebola-virus-pseudotyped particles (EBOVpp), leading to the discovery of Maesa perlarius as an anti-
EBOV plant lead. The methanol extract (MPBE) of the stems of this plant showed an inhibitory effect
against EBOVpp, with an IC50 value of 0.52 µg/mL, which was confirmed by testing the extract
against infectious EBOV in a biosafety level 4 laboratory. The bioassay-guided fractionation of MPBE
resulted in three proanthocyanidins (procyanidin B2 (1), procyanidin C1 (2), and epicatechin-(4β→8)-
epicatechin-(4β→8)-epicatechin-(4β→8)-epicatechin (3)), along with two flavan-3-ols ((+)-catechin (4)
and (−)-epicatechin (5)). The IC50 values of the compounds against pseudovirion-bearing EBOV-GP
ranged from 0.83 to 36.0 µM, with 1 as the most potent inhibitor. The anti-EBOV activities of five
synthetic derivatives together with six commercially available analogues, including EGCG ((−)-
epigallocatechin-3-O-gallate (8)), were further investigated. Molecular docking analysis and binding
affinity measurement suggested the EBOV glycoprotein could be a potential molecular target for 1
and its related compounds.
Keywords: anti-Ebola virus acti
Why Choose Us
- 100% non-plagiarized Papers
- 24/7 /365 Service Available
- Affordable Prices
- Any Paper, Urgency, and Subject
- Will complete your papers in 6 hours
- On-time Delivery
- Money-back and Privacy guarantees
- Unlimited Amendments upon request
- Satisfaction guarantee
How it Works
- Click on the “Place Order” tab at the top menu or “Order Now” icon at the bottom and a new page will appear with an order form to be filled.
- Fill in your paper’s requirements in the "PAPER DETAILS" section.
- Fill in your paper’s academic level, deadline, and the required number of pages from the drop-down menus.
- Click “CREATE ACCOUNT & SIGN IN” to enter your registration details and get an account with us for record-keeping and then, click on “PROCEED TO CHECKOUT” at the bottom of the page.
- From there, the payment sections will show, follow the guided payment process and your order will be available for our writing team to work on it.