tcdb.org. a Transporter classes 6 and 7 have not been assigned in the TC system yet and therefore are
not listed here. b Auxiliary proteins facilitate transport via established transport systems and therefore are not counted as a separate system. Of the channel proteins, almost all are alpha-type channels (Subclass 1.A). A few outer membrane porins (Subclass 1.B) were identified, but these were not examined more closely because of the recent extensive studies of Bhat et al. . No potential channel-forming toxins (Subclass 1.C) were detected. The MG132 Secondary carriers include mostly symporters (importers) and antiporters VX-770 (exporters), while almost all primary active transporters are ATP-dependent (Subclass 3.A). However, a smaller percentage may be oxidoreduction driven (Subclass 3.D) or decarboxylation driven (Subclass 3.B). Among the seven group translocation proteins, two belong to the phosphotransferase system (Subclass 4.A), while five may be acyl CoA ligase-coupled transport systems (Subclass 4.C). Of the ten proteins possibly functioning as transmembrane electron flow carriers, all ten are likely to carry an electron pair (Subclass 5.A). None is likely to be a single electron carrier (Subclass 5.B). Eight auxiliary transport proteins (Subclass 8.A)
and ten recognized transporters of unknown mechanism of action (Subclass 9.A) were also identified. Substrates transported by Mxa Table 5 and Figure 5 show numbers of transport proteins Y-27632 2HCl in Sco organized according to substrate types. Transporters that utilize inorganic molecules as substrates make up a large portion of all RG-7388 price transport proteins found in Mxa. Cation-specific transporters (23.7% — 84 total) are split evenly between primary and secondary carrier
systems (36 and 38 proteins, respectively) with only six recognized channels. There are markedly fewer inorganic anion transporters (5.1% — 18 total), including 6 primary carriers and 10 secondary carriers. In comparison, there are relatively few electron transport systems in Mxa. Table 5 Counts of Mxa transport proteins according to substrate type Substrate No. of proteins of indicated type acting on substrate type Channels/Pores Primary carriers Secondary carriers Group translocators Transmembrane electron flow carriers Auxiliary proteins (Putative) Poorly characterized Total no. of systems I. Inorganic molecules A. Nonselective 3 3 B. Cations 6 36 38 1 3 84 C. Anions 6 10 2 18 D. Electrons 4 3 7 II. Carbon sources A. Sugars & polyols 4 2 2 8 B. Monocarboxylates 0 C. Di- & tricarboxylates 1 1 D. Organoanions (noncarboxylic) 2 2 E. Aromatic Compounds 4 4 III. Amino acids & their derivatives A. Amino acids & conjugates 6 14 20 B. Amines, amides, polyamines, & organocations 1 1 C.