All strains grew at temperatures between 15 and 42°C and in the presence of up to 5% NaCl. The putative type strains REICA_142T (group-I) Alpelisib molecular weight and REICA_082T (group-II) were resistant to ampicillin (25 μg), colistin sulphate (100 μg), kanamycin (30 μg), nitrofurantoin (50 μg) and streptomycin (25 μg). However, they were sensitive to rifampicin
and gentamicin (25 μg ml-1), chloramphenicol (50 μg) and tetracycline (100 μg). Strain REICA_082T was resistant to nalidixic acid (30 μg). On the other hand, strain REICA_142T was not. All group-I and group-II strains were catalase-positive and oxidase-negative and revealed physiological and biochemical characteristics similar to those of other strains of the genus Enterobacter[21, 22]. They could be differentiated
from species in closely-related genera, i.e. Klebsiella, Escherichia Selleck YM155 and Salmonella, as follows. The novel (group I and II) Enterobacter species were positive for arginine dihydrolase, showed motility and were negative for the utilization of quinic acid. In contrast, Klebsiella species are non-motile (except for Klebsiella mobilis), are arginine-negative and are capable to utilize quinic acid. The novel (group I and II) species produced acetoin (Voges-Proskauer test) but not indole. In contrast, Escherichia species are acetoin-negative but produce indole. Interestingly, indole production has also been observed in Cronobacter species,
and hence the two new species were differentiated from Cronobacter. The group-I and group-II strains were all negative for the production of hydrogen sulphide, where, Janus kinase (JAK) in contrast, species of Salmonella are positive. Notwithstanding the limitations of the API 20E biochemical test database, it was applied for all strains of group I and II, next to the closely-related comparator strains (Table 2). On the basis of the API 20E system, the six strains fell precisely into the two groups (I and II), as delineated in the foregoing. These were differentiated by the following characteristics: group-I strains REICA_142T, REICA_084 and REICA_191 were positive for D-alanine, L-alanylglycine, L-aspartic acid and L-glutamic acid. At least one of these strains was also positive for the utilization of cis-aconitic acid and find more L-histidine. On the other hand, the group-II strains REICA_082T, REICA_032 and REICA_211 could utilize the following substrates as sole carbon sources: D-raffinose, malonic acid, β-hydroxybutyric acid, Tween 40, L-proline, inosine and thymidine. At least one of these strains was positive for the utilization of D-melibiose, α-cyclodextrin, acetic acid, formic acid and glycogen. The discriminatory properties of the two novel species and closely related species are given in Table 2.