https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Catalytic efficiency of soil enzymes explains temperature sensitivity: Insights from physiological theory https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:47997 Tue 14 Feb 2023 16:15:07 AEDT ]]> How different are the arsenic fractions inhibit alkaline phosphatases on aggregates scale? https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:39230 −1 of As(V)]. Besides, it was observed that available soil phosphorus could positively affect the relative content of water-soluble, exchangeable and carbonate-bound arsenic. In the kinetics experiment, both the Michaelis-Menten constant (Km) and maximum reaction velocity (Vmax) of ALP increased with increasing As(V) concentration under four months ageing for each size aggregate. Multiple linear stepwise regression analysis between kcat and the relative content of arsenic fraction indicated that carbonate-bound arsenic is the main fraction that inhibited the kcat for macroaggregates (> 0.25 mm size). For soil aggregates of 0.1–0.25 mm size, kcat increased with an increase in arsenic residual fraction. As for aggregates <0.1 mm size, Fe and Mn oxide-bound fraction is the main fraction that inhibited the kcat. Overall, this study suggests carbonate-bound and Fe and Mn oxide-bound arsenic fractions could decrease the ALP activities via a decrease in the catalytic efficiency in macroaggregates and <0.1 mm size aggregates, respectively. Besides, available phosphorus should be considered as the main factor when assessing As biotoxicity and mobility.]]> Tue 09 Aug 2022 14:08:44 AEST ]]>