Precore/core mutations of hepatitis B virus genotype D arising in different states of infection.
PMID: 35415256
2022
Clinical and experimental hepatology
Introduction: In a study conducted in the Korean population, the five HBcAg mutations P5H/L/T, E83D, I97F/L, L100I, and Q182K/Stop were significantly more frequent in subjects with chronic hepatitis and cirrhosis.
A nuanced role of the small loop of hepatitis B virus small envelope protein in virion morphogenesis and secretion.
8Discussion: Naturally occurring core mutants I97L (isoleucine to leucine) or F97L (phenylalanine to leucine), exhibited a so-called ""immature secretion"" phenotype, which allows excessive secretion of virions containing an immature genome."
Discussion: A pre-S1 envelope mutation A119F, changing an alanine (A) to a phenylalanine (F), can erase the immature secretion phenotype of the mutant I97L and successfully restore the wild-type-like selective export of the mature genome.
Binding of a Pocket Factor to Hepatitis B Virus Capsids Changes the Rotamer Conformation of Phenylalanine 97.
Introduction: Naturally occurring point mutations like HBc-F/I97L with an immature secretion phenotype or point mutations with a low secretion phenotype, such as HBc-L60V and HBc-P5T, are located in the area surrounding the pocket.
Amino Acid Polymorphism in Hepatitis B Virus Associated With Functional Cure.
PMID: 34352407
2021
Cellular and molecular gastroenterology and hepatology
Abstract: CONCLUSIONS: The I97L substitution reduces the level of cccDNA through the generation of immature virions with single-stranded genomes.
Abstract: HBV-I97L exhibited lower infectivity than HBV-I97wt in both infection systems with reporter HBV and cell culture-generated HBV.
Abstract: In this study, we attempted to identify the point at which I97L affects the hepatitis B virus (HBV) life cycle and to elucidate the underlying mechanisms governing the stabilization of hepatitis.
Abstract: METHODS: To confirm the clinical features of I97L, we used a cohort of hepatitis B e antigen-negative patients with PMID: 33803998
2021
Microorganisms
Result: Indeed, a previous study reported that C-I97F/L (A2189T/C or C2191T mutation) was the preC/C type found the most frequently in HCC patients in Korean chronic patients infected with genotype C2.
Result: The C-I97F/L in the C region, of which the frequency was significantly higher in rt269I strains than in rt269L strains (q = 0.047), is well known as the most frequently encountered HBcAg mutation, as mentioned in several studies leading to an immature secretion phenotype due to defective nucl
Naturally occurring core protein mutations compensate for the reduced replication fitness of a lamivudine-resistant HBV isolate.
Method: The core gene point mutations (P5T, S35T, S87G, I97L, Q177K) and the reversion mutations (T5P, T35S, Q79P, D83E, G87S, L97I, K177Q) were individually introduced into pCMVHBV-WT and pCMVHBV-GYF, respectively, by using QuikChange Site-directed Mutagenesis Kit (Stratagene) or Q5 Site-directed Mutagenesis Kit (NEB).
Result: Among those, I97L has been reported to be associated with the increased HBV DNA replication in Huh7 cells, we thus first examined the potential role of I97L
Persistence of Hepatitis B Virus DNA and the Tempos between Virion Secretion and Genome Maturation in a Mouse Model.
Figure: The SEAP activities in the sera indicated similar transfection efficiencies between WT and I97L in hydrodynamic delivery.
Figure: The red asterisk highlights the lessened abundance of fully mature full-length RC DNA associated with mutant I97L.
Figure: The right panel postulates that an overly efficient and less selective envelopment is the primary cause of the intracellular deficiency in the fully mature RC DNA in mutant I97L.
Figure: The viral DNA level of mutant I97L appeared to be much lower than those of WT HBV at day 3 or week 1 postinjection.
Figure: The viral DNA levels of mutant I97L, particularly the RC form, were greatly reduced in the liver at 3 dpi by Southern blotting.
Figure: Unlike the WT, mutant I97L displayed an excessive number
Early changes in quasispecies variant after antiviral therapy for chronic hepatitis B.
Abstract: Furthermore, several mutation patterns, such as cI97L and cP130T showed alterations in the secondary structure and predicted antigenicity of HBV protein.
The Correlation Between Hepatitis B Virus Precore/Core Mutations and the Progression of Severe Liver Disease.
PMID: 30406036
2018
Frontiers in cellular and infection microbiology
Introduction: Furthermore, five HBcAg mutations identified in a Korean population, P5H/L/T, E83D, I97F/L, L100I, and Q182K/Stop, were shown to be significantly enriched in HCC patients compared with patients at earlier disease stages, including those with cirrhosis and chronic hepatitis (Kim et al.,).
Core I97L mutation in conjunction with P79Q is associated with persistent low HBV DNA and HBs antigen clearance in patients with chronic hepatitis B.
PMID: 27998820
2017
Clinical microbiology and infection
Abstract: CONCLUSIONS: In patients with CHB, measurement of I97L and additional mutation P79Q would be useful for predicting persistent low HBV DNA, normal ALT, and HBsAg clearance.
Abstract: Cumulative incidences of persistent low HBV DNA and HBsAg clearance were significantly higher in patients with I97L than in those with wild-type I97 (p = 0.003 and p = 0.016, respectively), and even higher in those with P79Q.
Abstract: RESULTS: Incidence of Core mutation I97L differed significantly among groups: A, 30% (3/10); B, 36.4% (4/11); C, 83.3% (10/12) (p = 0.021).