Mohd Firdaus Abdul-Wahab

Universiti Teknologi Malaysia | UTM · Department of Biological Sciences

We report the complete genome sequence of Methylomonas sp. UP202 isolated from an urban waterway sediment in Singapore. The genome contains genes involved in methane, methanol, formaldehyde, and formate oxidation. It also contains genes utilizing various nitrogen sources such as nitrogen, nitrate, nitrite, urea, and ammonium.

Palm Oil Mill Effluents (POME) serve as suitable substrates for methane gas production through anaerobic digestion. This process relies on a complex microbial community that plays a critical role in ensuring stable anaerobic digester operation and efficient biogas production. Among these microorganisms, methanogenic archaea are pivotal in methane g...

Low-temperature bacteria have potential to produce biohydrogen and are often considered a potential renewable energy generator for the future. However, the bacteria have presented poor hydrogen yield due to slow metabolic rate and prolonged lag phase often caused by their restricted growth temperature limit. The ineffective search for new biocataly...

The slow metabolism of bacteria at low temperatures affects the catalytic efficiency of enzymes and productivity. This article investigates the use of a psychrotolerant bacteria (Klebsiella sp. ABZ11) for biohydrogen production, yield and scaling at optimal temperature, pH and glucose in a batch fermentation process within a 2-liter bioreactor usin...

This chapter describes microbiome engineering from the systems approach on how a well‐rounded and holistic approach can increase the chances of success in the field. It also describes methods such as the increasingly popular “design–build–test–learn” for rational engineering of microbiomes, and introduces tools for deeper understanding of the phyto...

Biohydrogen production through dark fermentation is very attractive as a solution to help mitigate the effects of climate change, via cleaner bioenergy production. Dark fermentation is a process where organic substrates are converted into bioenergy, driven by a complex community of microorganisms of different functional guilds. Understanding of the...

Harmful algal blooms (HABs) were not new to the tropical semi-enclosed Johor Strait, with incident records that could trace back to the 1980s. HAB monitoring in the area, often, is reactive, focusing only on HAB taxa previously causing problems but neglecting potential emerging HABs. To develop datasets on HABs that can better inform and improve ma...

Improvements in biohydrogen production from palm oil mill effluent (POME) has been achieved by optimizing the physicochemical conditions, using an enriched sludge as inoculum. Enrichment of biohydrogen-producing communities in the sludge was first carried out by heat treatment and acclimatization to POME. Response surface methodology (RSM) was then...

The Johor Strait has experienced rapid development of various human activities and served as the main marine aquaculture area for the two countries that bordered the strait. Several fish kill incidents in 2014 and 2015 have been confirmed, attributed to the algal blooms of ichthyotoxic dinoflagellates; however, the cause of fish kill events after 2...

High resolution Chlorophyll-a (Chl-a) can indicate the trophic status of the water and provide useful information on optical features of water body in water quality monitoring. Remote sensing has great potential to offer the spatial and temporal coverage needed. Over the last decades the Sea WIFS and MODIS were applied, but not suitable due to the...

Fermentative H2 production was studied using raw POME as the substrate with heat-shock pre-treated POME anaerobic sludge acted as the inoculum. The effect of crucial operating variables (initial pH of medium, incubation temperature, and inoculum size) on H2 production was studied using Box−Behnken Design. A second-order polynomial regression model...

The first layer of defense that plants deploy to ward off a microbial invasion comes in the form of pattern-triggered immunity (PTI), which is initiated when the pattern-recognition receptors (PRRs) bind with the pathogen-associated molecular patterns (PAMPs) and co-receptor proteins, and transmit a defense signal. Although several plant PRRs have...

Commercial water vending machines are gaining popularity nowadays among the general public, probably due to the ease of obtaining clean drinking water. However, improper maintenance of the machines can lead to bacterial contamination. Hence, this study aimed to investigate and determine the microbiological characteristics of drinking water from Wat...

Hydrogen gas (H2) is a clean fuel and contained a relatively high energy density which is about 142 kJ g⁻¹. Recently, increasing attention has been given to the production of H2 from biological route. The biological H2 (biohydrogen) process is an H2 production by microorganisms that utilize renewable energy resources as substrates. Possible biohydr...

The global rise in demand for fats and oil has made the palm oil industry grown tremendously over the last decades in countries like Indonesia, Malaysia, and Thailand. Malaysian agro-industrial sector alone accounts for about 51% of the world’s palm oil production and 62% of the world’s export. The sector has generated billions of dollars in revenu...

Access to the portable drinking water is of paramount importance and remains major challenge globally. Water vending machine (WVM) could supplies drinking water to the community but the bacterial growth in WVM is of great health risk requires urgent attention. Chlorhexidine zinc-modified kaolinite (C-Zn-Kao-t1) was prepared, characterized and studi...

Copolymer of polyacrylonitrile grafted with cellulose (AN-g-cellulose) was modified by reacting with hydroxylamine hydrochloride at pH 6, to functionalize it with amidoxime functional groups. Fourier Transform Infrared (FTIR) spectroscopy analysis was carried out to characterize the AN-g-cellulose to confirm the presence of amidoxime groups. Water...

Heat shock protein 47 (HSP47), a noninhibitory serine protease inhibitor (SERPIN, clade H1) family member, is a unique collagen‐specific molecular chaperone. The binding of HSP47 to collagen has been the subject of intense investigation, as it binds to and only to collagen. This binding specificity presents a relatively unexplored potential of usin...

This study aimed to investigate the ability of Citrobacter sp. strain L17 to decolourise azo dye in a rich medium (MP5) and three different minimal media (MMP5, MMGF11 and MM63) under microaerophilic and anaerobic conditions. Amaranth was used as the model dye in this investigation. Under microaerophilic condition, reactions were carried out at two...

The first layer of defence mechanism in plant known as pattern-triggered immunity (PTI) begins with the sense of pathogen-associated molecular patterns (PAMPs) by pattern-recognition receptors (PRRs). During the event PRRs bind with PAMPs and recruit co-receptor protein to activate the defence signal. To understand the mechanism properly, modeling...

Toxicity and mobility of silver nanoparticles (AgNPs) vary in different surrounding environments. Surface coatings or functionalization, temperature, pH, dissolved oxygen concentration, nanoparticle concentration, the presence of organic matter, and ionic strength are factors which dictate the transformation of AgNPs in terms of aggregation and sta...

Polyhydroxyalkanoates (PHAs) are biopolymers which have similar characteristics with petrochemical plastics but a step better due to its biodegradable property. A total of 23 strains were isolated from two different brackish sources. In order to detect the PHAs granules, the PHAs producing bacteria were first screened with Sudan Black B staining. T...

Aims: This study aimed at investigating the various hydrogen-producing bacteria isolated from three different bovine manure samples (dairy cow, feedlot cow and free grazing cow manures). Methodology and results: Nutrient broth (NB) and Reinforced Clostridium medium (RCM) broth were used for the isolation of facultative and strict anaerobic bacteria...

Climate change is a natural phenomenon where significant change in weather patterns in a certain region of the world is observed. Interestingly, the earth's climate has changed throughout its history mostly as a result of minor variations in the earth's orbit that change the amount of solar energy it received. Only recently, however, climate change...

This article reports on the refinement of selected VI for detecting and mapping of snow algae growth using multi-temporal Landsat Thematic Mapper (TM), archived from early 80’s to the recent Landsat-8 Operational Land Imager (OLI). In-situ spectral radiometry samples during UTM-Antarctica summer 2015 expedition were used in air-to-ground correlatio...

Background/purpose: Currently, silver nanoparticles (AgNPs) have gained importance in various industrial applications. However, their impact upon release into the environment on microorganisms remains unclear. The aim of this study was to analyze the effect of polyvinylpyrrolidone-capped AgNPs synthesized in this laboratory on two bacterial strain...

Environmental management is crucial for sustainable growth and development. The use of microorganisms to clean up contaminated environment provides cheap alternative method to the conventional treatment methods. But the choice of easily grown, viable and effective natural occurring microorganism to do the cleaning is a major challenge. In this arti...

A double-chambered membrane microbial fuel cell (MFC) was constructed to investigate the potential use of natural microflora anaerobic palm oil mill effluent (POME) sludge and pure culture bacteria isolated from anaerobic POME sludge as inoculum for electricity generation. Sterilized final discharge POME was used as the substrate with no addition o...

The aim of this study was to isolate and characterize psychrotrophic bacteria resistant to antibiotic and metals from cold samples of refrigerated spoiled food and ice. Two isolates named H and F were successfully isolated from samples incubated at 10°C and 4°C, respectively. Both isolates were able to grow at 4°C, 10°C, 20°C and 30°C and exhibited...

Human lysyl-tRNA synthetase (hLysRS) is known to interact directly with human immunodeficiency virus type-1 (HIV-1) GagPol polyproteins, and both hLysRS with tRNA(Lys3) are selectively packaged into emerging HIV-1 viral particles. This packaging process appears to be mediated by contact between the motif 1 helix h7 of hLysRS and the C-terminal dime...

Heat shock protein 47 (HSP47) is a single-substrate molecular chaperone crucial for collagen biosynthesis. Although its function is well established, the molecular mechanisms that govern binding to procollagen peptides and triple helices in the endoplasmic reticulum (followed by controlled release in the Golgi) are unclear. HSP47 binds procollagen...

Citrobacter freundii A1 isolated from a sewage treatment facility was demonstrated to be able to effectively decolorize azo dyes as pure and mixed culture. This study reports on the investigation on the enzymatic systems involved. An assay performed suggested the possible involvement of flavin reductase (Fre) as an azo reductase. A heterologouslyex...

This paper focuses on the degradation of azo compound C.I. Acid Red 27 (AR27, amaranth) by the recombinant enzyme flavin reductase (FRE) from Citrobacter freundii strain A1. The enzyme was obtained via re-transformation of recombinant plasmid pET-43.1c(+)freBP containing the flavin reductase gene (fre) into E. coli NovaBlue. The plasmid was subsequ...

Splicing system was originally developed by Tom Head in 1987 as the generative capacity of systems of restriction enzymes acting on DNA molecules. Splicing system can be modelled mathematically. The language which results from a splicing system is called a splicing language. This language can further be analyzed using concepts in formal language th...